Islamic State has claimed responsibility for a series of terror attacks in Sri Lanka which killed at least 359 people including 45 children and eight Britons.

Near-simultaneous explosions rocked churches and hotels on Easter Sunday with IS releasing a video showing who it claimed were the eight suicide bombers.

Police in Colombo have detained 58 people in connection with the bombings, while specialist officers from the Metropolitan Police’s Counter Terrorism Command have been sent to the country to support the bereaved and Scotland Yard has asked for images or video taken during the attacks.

Among the British victims were Anita Nicholson, her son Alex, 14, and daughter Annabel, 11, who died when one of seven suicide bombers struck as they ate breakfast at the Shangri-La hotel in Colombo.

Londoner Matthew Linsey’s daughter Amelie, 15, and son Daniel, 19, were killed in the same blast on the final day of their holiday.

GP Sally Bradley and her husband Bill Harrop, a retired firefighter, from Manchester, died in the Cinnamon Grand Hotel bombing.

The eighth victim is reported to be Lorraine Campbell, 55, from Manchester, with the Daily Mail saying she was staying at the Cinnamon Grand Hotel on a business trip.

Her son Mark told the paper: “I have been told it is her. She has been taken in a terrible way.”

Police have appealed for anyone with images or video from the period surrounding the attack to contact them – and officers have been sent to airports in the UK to speak to anyone returning from Sri Lanka.

Sri Lanka terrorist attacks
Ben Nicholson with wife Anita, son Alex, 14, and daughter Annabel, 11. The lawyer’s wife and two children were among nearly 300 people killed in the series of terror attacks in Sri Lanka (Family handout/PA)

Alexis Boon, of the Met Police Counter Terrorism Command, said: “We are specifically looking for images and footage taken at the scenes of the incidents in Sri Lanka, immediately prior to, during, or after the attacks on 21 April.

“The material will be looked at by officers from the Met’s Counter Terrorism Command, to assess it for use in any subsequent coronial process.”

MPs observed a minute’s silence in the Commons on Tuesday in memory of those killed in the Sri Lanka terror attacks, with Foreign Secretary Jeremy Hunt calling it a “truly heartbreaking situation”.

He said that in addition to the eight Britons who died, a locally employed British Council employee was “in hospital with his wife, both with serious injuries”.

Sri Lanka held a national day of mourning on Tuesday as the country’s prime minister Ranil Wickremesinghe warned that suspects armed with explosives were still at large.

Sri Lanka terrorist attacks
A book of condolence signed by Labour Leader Jeremy Corbyn at the Sri Lankan High Commission in London (Victoria Jones/PA)

As the country paid its respects, the inquiry into what the intelligence services knew about the attack continued.

Ruwan Wijewardene, minister of defence, said “weakness” within Sri Lanka’s security apparatus led to the failure to prevent the nine bombings.

He said: “By now it has been established that the intelligence units were aware of this attack and a group of responsible people were informed about the impending attack.”

The president Maithripala Sirisena went further, saying that officials who failed to share information would face “stern action”.