A man apparently set himself on fire outside Britain's Parliament on Friday and he was taken to a hospital with superficial burns, authorities said.

Police said the man was on fire "for a short time" in Parliament Square in the heart of London. Without saying specifically that the man attempted self-immolation, police said they did not believe anyone else was involved.

A police spokesman said the man's burns were superficial and "certainly not critical." He spoke on condition of anonymity in line with force policy.

Peace campaigner Brian Haw, 60, who lives on the square, said the man acted without warning at about 4 p.m. Haw and other demonstrators raced over to him, pushing him down to roll him on the ground and beating back the flames with a leather jacket.

"His head was burning away," Haw said. "It was quite shocking."

There was no immediate word on who the man was or why he would set himself on fire. But it follows two attempts at self-immolation by men who have been reported to be ethnic Tamils based in Britain.

On Feb. 14, a Tamil was arrested outside Downing Street, where the British prime minister lives, before he could set himself ablaze. That came days after a 26-year-old Sri Lankan protester poured gasoline over himself and burned to death outside the U.N. complex in Geneva.

Tamils have been holding steady protests over the Sri Lanka's military action against ethnic Tamils.

In Geneva, police found a five-page letter identifying the man and declaring that the self-immolation was to protest developments in the island nation.

Sri Lanka's government is fighting to crush the rebels and end their 25-year campaign for an independent homeland for the country's ethnic minority Tamils, who have suffered marginalization under the country's majority ethnic Sinhalese. More than 70,000 people have been killed in the violence.