The horrific attack targeted three churches and three luxury hotels during the early hours of Easter Sunday.
At least two of the hotels and one of the churches are in the capital, Colombo. Another church is in Negombo, north of Colombo.
Sri Lankan police officials told Reuters in just one church, St. Sebastian’s in Katuwapitiya, north of Colombo, more than 50 people had been killed.
The Foreign Office said it was “urgently seeking” information from authorities in Sri Lanka.
A spokeswoman said: “We are aware of reports of a number of explosions in Sri Lanka, including Colombo, and we are urgently seeking information from the local authorities.
“British nationals in Sri Lanka should follow the instructions of the local authorities and check FCO travel advice for updates.”
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