Pro-Tamil demonstrators have caused traffic chaos as they mounted a sit-down protest on a busy road opposite the Houses of Parliament.
Hundreds of protesters moved en masse to occupy parts of Bridge Street and Westminster Bridge, a major thoroughfare through central London.
On Sunday, 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.
Earlier on Monday, Sri Lanka's state TV announced that the Tamil Tigers' leader. Velupillai Prabhakaran, had been killed by army troops.
Traffic in the central London area was diverted and a large police presence gathered around the protesters with police helicopters circling above Parliament Square.
Protesters have been demonstrating in the Square for a number of weeks to draw attention to the plight of Tamils in Sri Lanka.
A police source said the protesters, accompanied by a large number of children, moved en masse at around 4pm on Monday from the grassy area in the square to sit down on the neighbouring road.
Many prams could be seen among a sea of flags and banners belonging to the seated demonstrators.
A London bus and a number of vans cut off by the protest were sitting motionless at the heart of the demonstration.
