A union flag flies at half-mast with the pods of the London Eye seen in the background in central London on March 23, 2017 the day after the March 22 terror attack in Westminster claimed at least three lives including that of police officer Keith Palmer. Pic/AFP 

London: The Islamic State has claimed responsibility for the terror attack in the heart of London that killed four people, the BBC reported.

"So-called Islamic State says it was behind attack in Westminster, according to a statement from the group," the BBC said.