THE identity of the Manchester suicide bomber who killed 22 people and injured 59, was quickly established after police found one key piece of evidence in his pocket.
The young man, named by British police as Salman Abedi, exploded a homemade bomb and died inside Manchester Arena at the end of Ariana Grande's performance on Monday night. UK police revealed Abedi was a 23-year-old British national of Libyan descent. He was born in Manchester and grew up alongside three siblings.
The Guardian reports a 23-year-old arrested in south Manchester on Tuesday morning in relation to the attack is still being questioned. It is believed to be Ismael Abedi, the brother of the attacker, but police are yet to confirm.
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A US intelligence official told NBC that Salman Abedi's bomb was "big and sophisticated" and used materials hard to obtain in Britain, which pointed to help from others.
Abedi also had ties to al-Qaeda, according to the official, and received terrorist training abroad.
Authorities were able to identify him using a bank card found in his pocket and confirmed his identity using facial recognition technology.
The official said members of Abedi's own family had informed on him in the past, telling British authorities he was dangerous.
According to ABC News in the US, British counterterrorism authorities had already identified Abedi as a potential threat, along with hundreds of others.
"Abedi was a terrorist suspect in the UK, MI5 were aware of him," Robin Simcox, a terrorism and national security analyst at The Heritage Foundation said.
"They were aware that he posed a potential threat but they didn't think he posed an imminent threat that he proved himself to do in Manchester."
Intelligence agents are now investigating reports the football-obsessed Abedi slipped into Syria while visiting relatives in Libya several times in recent years, The Sun reports.
His home in the Manchester suburb of Fallowfield was one of two that police raided in relation to the attack on Tuesday.
To outsiders Abedi was seen as the quiet one in the family. According to the Daily Beast, his older brother Ismael was the more outspoken one of the boys and his sister Jomana was known for her glamorous social media accounts that channel Keeping Up With The Kardashians.
His father, known as Abu Ismail, was a prominent member of the community, who used to perform the call to prayer at Didsbury Mosque and Islamic Centre.
The imam of the mosque, Mohammed Saeed told ABC, that Abedi became angry with him after he gave a sermon in 2015 in which he criticised Islamic State.
"He was showing me hate, he hated me basically," Saeed said. "I was shocked, shocked and angry. All innocent lives matter."
The mosque is located in an area of Manchester known as Moss Side, which one expert told ABC was considered to be a hot bed of Islamic State recruitment.
Neighbours say Abedi, who studied business and management at Salford University before dropping out, had grown a beard in the last 12 months and had begun acting strangely.
"A couple of months ago he [Salman] was chanting the first kalma [Islamic prayer] really loudly in the street. He was chanting in Arabic," Lina Ahmed told The Sun.
"He was saying 'There is only one God and the prophet Mohammed is his messenger'."
Another neighbour, Leon Hall, said the young man "had an attitude problem."
BOMB TIMED TO INFLICT 'MAXIMUM CARNAGE'
British Prime Minister Theresa May said Abedi deliberately chose to detonate an explosive at the end of the show to inflict "maximum carnage."
Islamic State has claimed responsibility for the bombing, but Chief Constable Ian Hopkins said it was not clear yet how many other people were involved in the planning.
"Our priority, along with the police counterterrorist network and our security partners, is to continue to establish whether he was acting alone or working as part of a wider network," he said Tuesday afternoon.
The Guardian reports a second terrorist attack could be imminent and the threat level has been raised from severe to critical. The threat level has not been this high since 2007.
Ms May said she did not want people to be alarmed, but a military presence on the streets would be boosted. There will be heightened security at the FA Cup final at Wembley Stadium in London, and this weekend's premiership rugby final at Twickenham Stadium.
She told media "the police have asked for authorisation from the secretary of state for defence to deploy a number of military personnel in support of their armed officers".
Greater Manchester Police Deputy Chief Constable Ian Pilling said in a statement raising the threat level to critical would support the ongoing investigation.
"People across Greater Manchester have seen an increased police presence throughout the day and this will continue. They will be seen at key locations across the region," he said.
"We are continuing to work with the national counter terrorism policing network and UK intelligence services as part of the response to dealing with the tragic events that took place."
Ms May said the attack could have involved a "wider group of individuals" and was among "the worst terrorist incidents" in UK history.
"A single terrorist detonated his improvised explosive device near one of the exits of the venue, deliberately choosing the time and place to cause maximum carnage and to kill and injure indiscriminately," she said outside her official residence at 10 Downing St, London.
"It is now beyond doubt that the people of Manchester and of this country have fallen victim to a callous terrorist attack, an attack that targeted some of the youngest people in our society with cold calculation.
"As so often, while we experience the worst of humanity in Manchester last night, we also saw the best.
"The cowardice of the attacker met the bravery of the emergency services and the people of Manchester.
"Let us remember those who died and let us celebrate those who helped safe in the knowledge that the terrorists will never win and our values, our country and our way of life will always prevail."
CROWDS FLEE AFTER BLAST
Police said the blast occurred in the foyer of the 21,000-capacity indoor arena, a covered area which links to Victoria railway station.
Some concertgoers mistook the massive bang for exploding balloons, which had been dropped onto the crowd at the end of the performance.
The bomb sent nuts and bolts flying, witnesses said, and bloodied bodies were strewn across the floor after the blast about 10.30pm Monday (7.30am Tuesday, Australian eastern standard time). Some fans were trampled as panicked crowds tried to flee the venue.
"There was an explosion heard as we were leaving the arena and then another one when we got outside," concertgoer Sibion Joyce, from Bury in Greater Manchester, told news.com.au.
"Everyone went still at first and then the panic kicked in and people started running and screaming to get out of the arena, there were lots of young people.
"I was scared, at first we didn't think it was anything as serious as this but when the swarms of emergency services arrived it was evident it was a serious incident."
The 22-year-old added: "I was trying to get home from Manchester for two hours, there is a three-mile radius cordoned off."
British police arrested a 23-year old man in Chorlton, south Manchester, in connection with the attack and also raided properties in the suburbs of Whalley Range and Fallowfield, where a controlled explosion took place so police could gain safe access.
Local residents said a "group of people" were taken away by police after the explosion, according to the BBC.
"I've been talking to the police about the investigation that is continuing, and they and the security services are working, obviously, to identify whether there was a wider group of people involved in this particular incident," Ms May told the BBC.
Stories of the 22 victims are slowly emerging, including that of an eight-year-old girl.
One brave aunt Kelly Brewster, 32, was killed after reportedly trying to shield her niece from the blast. Other victims include Georgina Callander, 18, John Atkinson, 26, Alison Howe, 44, Lisa Lees, 43 and Saffie Rose Roussos, 8. Megan Hurley, from Liverpool, is also one of the victims.
Twelve people under the age of 16 were among the 59 injured.
US President Donald Trump condemned the people behind the attack as "evil losers".
"I won't call them monsters because they would like that term. I will call them losers," he said while on his first international trip as President in the Middle East.
'CLASSIC ISLAMIC STATE MOVE'
According to international policy organisation the Counter Extremism Project the attack fits a classic pattern of terrorists targeting crowded areas in order to maximise civilian casualties.
The attack, the deadliest in the United Kingdom since the 7/7 bombings in 2005, came as IS claimed one of its "soldiers of the caliphate" had placed bombs in a "gathering of crusaders".
In its Terror Targets in the West: Where and Why, the CEP note airports and planes are no longer the only target of groups such as Islamic State and al-Qaeda.
Law enforcement and military installations and personnel are also targets along with crowded areas and events.
Just two months ago, British-born Khalid Masood rammed a car into a crowd of pedestrians on London's Westminster Bridge, killing five people.
Speaking to Channel 9 yesterday, former ASIO officer Warren Reed said the Manchester bombing seemed to be a classic terrorist operation causing mass disturbance and panic.
"It seems to be a classical move in the sense that it caused people to react and panic inside the venue," he said.
"It's a pretty classic Islamic State tactic," he said.
Mr Reed said it was also impossible for police to watch everybody and while we couldn't live in a state of fear it was important that people reported any suspicious activity.
"We don't want to become an informer society ... but we do need to be willing as individuals to ring police and discuss suspicions we have," he said.
Meanwhile the Manchester bombing has sparked a security review of upcoming public events across Australia, it has emerged.
ASIO and the Australian Federal Police have been ordered to reassess the terror threat in the wake of yesterday's devastating attack, The Australian reported.
NSW police said there was no specific domestic threat and there has not been any order for upgrades or strengthening of the current security measures in place.
The review is expected to target events such as Sydney's Vivid Festival which starts this Friday as well as major sporting events.
IS SAYS BOMBER TARGETED CONCERT 'GATHERING'
Meanwhile Islamic State released a statement to sympathetic news agency Amaq, praising the bomber.
"With Allah's grace and support, a soldier of the Khilafah (Caliphate) managed to place explosive devices in the midst of the gatherings of the crusaders in the British City of Manchester, in revenge of Allah's religion, in an endeavour to terrorise the mushrikin, and in response to their transgressions against the lands of the Muslims," the statement read.
"Mushrikin" refers to people who do not worship Allah, who fundamentalist Muslims believe is the one and only god.
"The explosive devices were detonated in the shameless concert arena, resulting in 30 (sic) crusaders being killed and 70 others being wounded," the statement continued.
"And what comes next will be more severe on the worshippers of the Cross and their allies, by Allah's permission. And all praise is due to Allah, Lord of creation."
The US singer is devastated following the attack and yesterday tweeted how sorry she was that it took place.
Grande tweeted after the attack that she was "broken" and "so, so sorry".
broken.— Ariana Grande (@ArianaGrande) May 23, 2017
from the bottom of my heart, i am so so sorry. i don't have words.
The singer has since reportedly landed back in Florida after flying in on a private plane.
Grande, her mother and dog were met on the tarmac in Boca Rato by family members and rapper Mac Miller who has is dating the singer, E! News reported.
"It was a very emotional reunion and they stood talking for a minute before getting into the car," the source told E! News. "Ariana looked exhausted and like she didn't get much sleep."
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