UK raises security level to 'critical' following Manchester attacks

The UK raised security to its highest possible level on Tuesday, with chiefs fearing more attacks - such as the one carried out in Manchester on Monday night - could be imminent.

The government has only raised the terrorist threat level to "critical" twice before, which means that soldiers will deployed to streets in the UK to guard certain locations.

Prime Minister Theresa May announced that troops would take over guard duties from armed police at certain sensitive sites.

"This morning I said that the Joint Terrorism Analysis Centre, the independent organisation responsible for setting the threat level on the basis of the intelligence available, was keeping the threat level under constant review," May said in a statement. 

"It has now concluded, on the basis of today's investigations, that the threat level should be increased for the time being from severe to critical. This means that their assessment is not only that an attack remains highly likely, but that a further attack may be imminent."

May also praised emergency services for their response to Monday's tragedy.

Operation Temperer could see as many as 5,000 soldiers take part in guarding duties, as railway stations, airports and other sensitive locations such as music concerts and sports events.

Police would instead be able concentrate their resources on the hunt for more suspects and carry on their work in other areas.

May will chair an emergency meeting with the Cobra committee at 9.30am tomorrow, the government said on Tuesday evening, to review the security situation.

It follows a bomb attack at a music concert on Monday night in Manchester, which left at least 22 people dead, including children.

Police identified the suspected suicide bomber as 22-year-old Salman Abedi, a British man born to Libyan parents and who lived in the city.

The Islamic State group issued a statement claiming responsibility for the attack, but it is still not known if the organisation ordered the bombing or if Adedi acted alone. 

The attack appeared aimed at killing as many teenage concertgoers as possible.

Manchester, meanwhile, has been in shock but also stood defiant. 

A vigil in the city centre was held early Tuesday evening to remember the victims and bring Manchester together, with local poet Tony Walsh speaking at the ceremony.