Britain's most senior counter-terror police officer is appealing to the public to help prevent attacks.

Mark Rowley, assistant commissioner of London's Metropolitan Police, told the BBC Monday that cooperation between the police and the public was Britain's "greatest advantage" in the fight against terrorism. His comments follow attacks in France, Belgium and Germany by people inspired by the Islamic State group.

On Sunday, the Metropolitan Police Commissioner, Bernard Hogan-Howe, warned that a terrorist attack in Britain was a case of "when, not if."

Rowley says some 3,600 contributions — or tips — from the public take place every day, but recent attacks show that extra vigilance is necessary. He encouraged people to call an anti-terror hotline if they see anything suspicious in their community.