London terror attack: 12 suspects arrested, May says 'enough is enough'

London : Twelve people have been arrested on suspicion of involvement in a terror attack in London which claimed seven lives before police shot dead three suspects, authorities said on Sunday.

Investigators raided several addresses in Barking, 14 km east of London Bridge where three men were gunned down after driving a white van into pedestrians and then stabbing people in a nearby market on Saturday night, reports Efe.

Nearly 50 people were injured in the terror attack in the heart of London.

British Prime Minister Theresa May said: "It's time to say enough is enough." She said the counter-terrorism strategy would be reviewed, the election campaign would resume on Monday and the parliamentary elections would be held as planned on June 8.

This is the third terror attack in Britain since March.

On March 22, six people, including a lone attacker, were killed and at least 50 people were injured in a similar attack on Westminster Bridge near Parliament. Then came the Manchester bombing.