UK police arrest three more in Manchester bombing investigation

Three men have been arrested in Manchester in connection with the attack that left at least 22 people dead at Manchester Arena.

Greater Manchester Police said the arrests were made in the south of the city, where a 23-year-old suspect – bomber Salman Abdi’s brother – was arrested on Tuesday in connection with the attack.

“Three police warrants were executed in south Manchester in connection to the ongoing investigation,” a spokesperson said.

Abedi killed 22 and injured 64 when he blew himself up outside an Ariana Grande concert on Monday night.

Investigators are working to establish whether the 22-year-old acted alone or was part of a wider terrorist network, raiding several properties across Manchester.

The UK terror threat level is now up to its highest level of "critical", meaning more attacks may be imminent. Military personnel are being deployed to protect key sites.

Amber Rudd, the home secretary, confirmed Abedi had recently returned from Libya and the nature of his attack suggested he may have had support.

"[Monday's attack] was more sophisticated than some of the attacks we've seen before, and it seems likely - possible - that he wasn't doing this on his own," she said.

“When this operation is over, we will want to look at his background and what happened, how he became radicalised and what support he might have been given.”

After a meeting of the Cobra emergency committee, Rudd said 984 members of the armed forces were being deployed, initially in London but then elsewhere. A number of troops later arrived to take up positions at the Houses of Parliament.

Abedi used a suitcase bomb packed with homemade explosives and nails for the attack – the same method used for Isis’ bombings at Brussels Airport and Molenbeek metro station last year.

It was detonated in the foyer between Manchester Arena and Victoria station shortly before it detonated amid Ariana Grande fans pouring out of the concert.

Isis claimed the attack was carried out by a “soldier of the caliphate” in a statement threatening further atrocities against “crusaders”.

Those injured in the bombing are being treated at eight Greater Manchester hospitals. Of those, 20 are in a critical condition, and some have lost limbs. The wounded include 12 children aged under 16, and several people remain missing.