An estimated 50,000 people, including NRI Labour MP Keith Vaz, staged a peaceful demonstration in the British capital, demanding an end to the fighting in Sri Lanka and resumption of peace talks between the government and the Tamil rebels.
The rally, mostly attended by members of the Tamil community, started at Atterbury Street, by the Tate Britain gallery and passed along the north bank of the River Thames to Temple Place.
Beating drums and waving flags, the demonstrators raised slogans demanding an end to the conflict in Sri Lanka.
"More than 50,000 were at the demonstration" yesterday, a spokesman for Metropolitan Police said today.
"There has been one arrest for possession of an offensive weapon," he said.
A spokesman of the demonstrators presented a petition to British Prime Minister Gordon Brown at Downing Street, urging the government to persuade Sri Lankan forces to declare a ceasefire.
It also urged British action to monitor the ceasefire by international community. The protestors sought immediate humanitarian relief and peace talks in the island nation.
International concerns over the humanitarian impact of Sri Lankan government's war against the LTTE rebels in the northern part of the island has been steadily rising.
The government had on Thursday given a 48-hour deadline to the LTTE to release civilians caught in the war, but the rebel outfit has failed to do so.