Britain to deploy armed forces following Manchester attack

During an address in front of the 10 Downing Street on Tuesday, May also raised the threat level from “severe” to “critical.”

"It is now concluded on the basis of today's investigations that the threat level should be increased for the time being from severe to critical," she said in a televised statement after a meeting of the government's crisis response committee. "This means that their assessment is not only that an attack remains highly likely but that a further attack may be imminent."

A suicide bomber with an “improvised” explosion device targeted a concert arena in Manchester as thousands of young people streamed from the venue on Monday.

Police later identified the suspected bomber as Salman Abedi, aged 22.

"The work undertaken throughout the day has revealed that it is a possibility we cannot ignore that there is a wider group of individuals linked to this attack," said the British premier.

The Daesh Takfiri group has claimed responsibility for the attack without publishing a name or picture of the attacker.

“I do not want the public to feel unduly alarmed. We have faced a serious terror threat in our country for many years and the operational response I have just outlined is a proportionate and sensible response to the threat that our security experts judge we face. I ask everybody to be vigilant and to co-operate with and support the police as they go about their important work," May said.

"We will take every measure available to us and provide every additional resource we can to the police and the security services as they work to protect the public."

KD