The British Police on Tuesday identified the suicide bomber responsible for the attack at an Ariana Grande concert in Manchester as Salman Abedi. Earlier in the day, police said they had arrested a 23-year-old man in connection with the attack that left 22 people dead. Almost immediately after, the Islamic State group claimed responsibility for the attack, which also injured 59, according to AP.

Abedi is believed to be a Libyan-origin resident of Manchester, BBC reported. Greater Manchester Police said they will share more details once the coroner confirms the accused’s identity. “With regards to last night’s incident at the Manchester Arena, we can confirm we have arrested a 23-year-old man in South Manchester,” the Greater Manchester Police said on Twitter.

After the arrest was made, Prime Minister Theresa May said that the security forces know the identity of the bomber and are working to find out if he was a part of any militant group, reported The Telegraph. Speaking outside Downing Street, May condemned the “cowardice” of the attacker and praised those who offered help.

“The spirit of Britain ... a spirit that through years of conflict and terrorism has never been broken and will never be broken,” said May. The prime minister added that the attacker deliberately chose the concert to cause “maximum carnage”.

While the suicide bomber is believed to have been killed when the device exploded, the police also found another explosive device at the venue only hours after the attack. However, they managed to carry out a controlled explosion and avoided further casualties. Monday night’s attack is considered to be the worst in Britain since July 2005, when suicide bomb attacks killed 52 people.