TORONTO - Thousands of Tamil-Canadians took part in a boisterous protest Wednesday at the Ontario legislature under the watchful eye of hundreds of police officers after another peaceful demonstration over the weekend turned into an impromptu storming of one of Toronto's busiest highways.

A constant rotation of protesters took turns at various megaphones chanting "Tamil Tigers, freedom fighters" and "no more genocide" for hours until their voices turned hoarse.

Hundreds of police officers, most of them in riot gear, kept watch by forming a perimeter around the peaceful demonstration. Several more officers on horseback stood ready nearby.

The protesters left the legislature Wednesday evening and marched through down several downtown streets as police closed the roads ahead of the banner-waving marchers.

The protesters returned to the legislature lawn following the march and were again ringed by hundreds of police.

At one point, police closed down the road in front of the nearby U.S. Consulate, which has been the scene of past protests by the Tamil community.

The heavy police presence comes after thousands of Tamil protesters overwhelmed a handful of police officers on bikes Sunday and swarmed onto a downtown Toronto highway, closing it for hours.

Leading up to Wednesday's protest, police had issued warnings that the city could see disruptions again, though protest organizers had not threatened similar road closures.

The Tamil community is calling on Ottawa to ramp up efforts to pressure the Sri Lanka government toward a ceasefire.

Protester Sahab Jesuthasan said he understands people are frustrated by the demonstrations but adds it's necessary to raise awareness.

"I think patience is wearing a little thin ... (but) people are finally asking why," he said.

"MPs are talking, the media is talking, people on the streets are talking. That's what we wanted."

People in the crowd carried posters displaying gruesome pictures of the dead and wounded, and accused the Sri Lankan government of atrocities. They said much of that can't be verified because the government is barring the international community and the media from the war zone.

Protester Thava Siva called on the government to hold Sri Lanka accountable, likening what is happening in his homeland to the Rwandan genocide.

"The international community is keeping the silence forever and ever," he said. "They're allowing this genocide to happen and later on they're going to say, `Sorry, we didn't know this happened in this large scale."'

Organizer Senthan Nada said while the intention was to have a peaceful assembly, he couldn't rule out further action because of the size of the crowd.

The red flags of Tamil Eelam were also prominently displayed Wednesday at the rally, as they have been at past rallies in both Toronto and Ottawa.

While the federal government has said those flags suggest to Canadians that the terrorist Tamil Tigers are taking part in the protests, organizers say the flags are those of the secessionist movement and not the terrorist group.

The protesters were also flying Canadian flags alongside those of Tamil Eelam.

The frustration over Sri Lanka's civil war boiled over Sunday after reports that an all-night artillery barrage in the country's war zone killed more than 370 people and forced thousands to flee to makeshift shelters along a beach.

Thousands of people, including many young children, barricaded the Gardiner Expressway, shutting the major route for hours.

Although the protesters were urging the federal government to take action through economic sanctions and sending aid, Wednesday's rally took place at the provincial legislature.

Nada said the demonstration was held in Toronto because the city has the largest Tamil community in Canada, and the province also has a responsibility to address their concerns.

Inside the legislature Wednesday, the government tabled a resolution expressing "deep concern about the humanitarian crisis in Sri Lanka." The resolution encouraged the federal government to get involved.

Nada praised the sentiment, but said it lacked action.

Premier Dalton McGuinty encouraged the UN Security Council to find a way for Canada and other countries to help civilians affected by the fighting in Sri Lanka.

McGuinty said he understands why people in Toronto are unhappy about the protests, especially Sunday's, but added it's important to recognize the underlying issue.

"According to the UN, what is unfolding in northern Sri Lanka is a bloodbath," he said.

"We have the responsibility to allow people to express themselves and to dissent in a lawful way, and I think we also share a higher responsibility to find a way to speak out as responsible global citizens in the face of a significant breach of human rights."

McGuinty said this is not a time for the international community to be silent, and he is in favour of the UN Security Council bringing countries together to help.

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