More than 1,000 Sri Lankan protesters chanted outside the British High Commission in the capital Colombo, with some throwing rocks and breaking two windows, a Reuters witness said.
Some protesters set fire to an effigy of British Foreign Secretary David Miliband and threw it over the compound's wall. Miliband has been critical of the Sri Lankan government's prosecution of the war, and Britain has backed calls for a war crimes probe.
Reuters
British anger at Sri Lanka protest
Britain has issued an angry rebuke to the Sri Lankan authorities after protesters attacked the UK's High Commission in Colombo.
The High Commission said it was an "outrage" that the demonstration was allowed to turn violent and damage British property.
The protest came hours after the rebel Tamil Tigers conceded defeat in their bloody 25-year conflict with Sri Lanka's government, which has claimed an estimated 70,000 lives.
More than 1,000 people massed outside the British High Commission building in the Sri Lankan capital, accusing the UK of supporting the Tamil Tigers.
The demonstrators burned an effigy of Foreign Secretary David Miliband, pelted the compound with rotten eggs and stones and sprayed graffiti. They carried placards with slogans reading "Hands off Sri Lanka, we are not your colony" and describing Mr Miliband as a "White Tiger".
After about an hour, the protesters dispersed, leaving damage to the compound's outer wall and a CCTV camera, although no members of staff were injured.
A High Commission spokesman said: "It is an outrage that the authorities allowed this demonstration to become so violent and to cause such damage to our property, in clear contravention of their responsibilities."
The British Government has pledged to give another £5 million in aid to Sri Lanka amid concerns for the safety of civilians who were trapped in the war zone in the north of the country.
Announcing the donation on Sunday, International Development Secretary Douglas Alexander said: "We must prevent this desperate situation descending into a humanitarian catastrophe."
The funding will go towards providing essentials such as shelter, water, sanitation and medical care and, when possible, supporting displaced people in making a "dignified and safe" return to their homes.
Press Association
