Streets were calm on Tuesday in the Sri Lankan capital of Colombo, after a day of clashes that killed seven people and injured more than 200, police said, in violence that prompted Prime Minister Mahinda Rajapaksa to resign.

As the nation battles its worst economic crisis in history, thousands of protesters defied curfew to attack government figures, setting ablaze homes, shops and businesses belonging to ruling party lawmakers and provincial politicians.

"The situation is calmer now, though there are still reports of sporadic unrest," said police spokesman Nihal Thalduwa.

About 200 people were injured in addition to the seven killed as violence flared nationwide, prompting imposition of an island wide curfew until Wednesday morning.

Rajapaksa on Monday said he has resigned from the post as violent protests broke out in the capital between his supporters and anti-government demostrators.

A government notification issued by order of President Gotabaya Rajapaksa on Monday night confirmed that the prime minister has resigned with effect from that day.

(With input from agencies)