LONDON - Hundreds of pro-Tamil demonstrators blocked traffic and clashed with police in the streets around Britain's Parliament on Monday.

This happened after news came from Sri Lanka that hundreds of their compatriots had died in intense shelling. Police said Monday evening that 36 people had been arrested and the protesters had been cleared from the roads.

A committed core of Tamil demonstrators has been camped outside Parliament for more than a month to demand that Britain intervene to stem the bloodletting in Sri Lanka, once part of the British Empire.

Placard-toting protesters surged into the street around Parliament on Monday morning, surrounding a bus and snarling traffic.

London's Metropolitan Police said they tried to corral the protesters back onto Parliament Square, a stretch of green in front of Britain's neo-Gothic legislature, but some demonstrators threw things at them.

Anger over the recent offensive has been felt in North America, too: Tamils blocked a major highway in Toronto on Sunday to protest the shelling.

It was among the latest in a series of international protests intended to keep the Tamils' plight in the international eye and to pressure Sri Lanka to agree to a humanitarian ceasefire.