TORONTO - The spectre of a banned terrorist group having taken part in a protest that shut down a Toronto highway was raised by the Conservative government Monday as Tamil-Canadians defended their controversial demonstration and said more action would be taken.

While politicians at all levels heaped scorn on the community for the unlawful blockade, remarks by a senior cabinet minister that Tamil Tiger flags were displayed Sunday on the Gardiner Expressway were dismissed by protesters as an attempt to shift the focus from the humanitarian crisis in Sri Lanka.

One day after their rage and desperation over the deaths of Tamils in the south Asian country sent thousands streaming onto the highway, protest organizers said more demonstrations would follow in an effort to force Ottawa to ramp up efforts to force a ceasefire.

What those rallies would look like, they warned, was unknown considering Sunday's highway shutdown wasn't planned.

The fight on Monday, however, also involved a flap over flags as Minister of International Co-operation Bev Oda said she noticed Tamil Tiger flags at the protests, including another one that shut down a major thoroughfare by the provincial legislature.

The Tamil Tigers were labelled a terrorist group by the Canadian government under Prime Minister Stephen Harper in 2006.

"I noticed in the coverage of the demonstrations over the weekend that Tamil Tiger flags were being flown which would say to Canadians that they are part, the terrorist organization is part of the demonstrations that happened," Oda said.

Siva Vimal, a 20-year-old Tamil protester, said "we can see that they are using the flag kind of like a shield to kind of divert any bad attention."

The red flags flown at the rallies -- that feature a tiger jumping through a ring of fire under two crossed rifles -- are those of the secessionist Tamil Eelam movement and not the terrorist group, Vimal said.

At issue is the flag that was originally created in 1977 for the Liberation Tigers of Tamil Eelam, although protesters say writing that linked the flag to the militant group was removed in 1990 when it became the symbol of Tamil Eelam.

Later in the day, Oda's tone was tempered, saying that while she saw flags belonging to the terrorist wing of the Tamils, the humanitarian needs in Sri Lanka should be the focus.

"Well, there were flags that have been used by the (Liberation Tigers of Tamil Eelam) or the Tamil Tigers... We saw them again yesterday," she said. "I think the major issue, the primary issue here is the concern of the civilian victims in Sri Lanka."

Some protesters chanted their support for the Tamil Tigers at Sunday's highway demonstration.

The thousands of people who flooded onto the Gardiner Expressway left only after receiving assurances that the Liberals would raise their plight in Parliament -- which both they and the NDP did during question period Monday.

The group originally said it would not leave until either Harper or a government representative spoke with them.

"We will have meetings with any Tamil community representative that (is) not part of a terrorist organization," Oda said in the House of Commons.

In a statement, Liberal Leader Michael Ignatieff said he would continue to press the Conservatives on the humanitarian crisis but distanced the party from the demonstration itself.

Ignatieff, who said the Liberals unequivocally condemn the Tamil Tigers, urged that future protests be lawful and stressed that Liberal MPs took no part in the protest.

The frustration over Sri Lanka's civil war boiled over 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.

Protesters in Canada dispute the number, saying the death toll is in the thousands.

There are few, if any, independent observers in the area, so information is sketchy.

Though Sunday's highway protest trapped dozens of motorists and created traffic headaches, the people who participated in the impromptu demonstration say it was necessary to bring attention to their demands.

Protesters are pushing the Canadian government for a host of political and economic sanctions against Sri Lanka, including recalling Canada's high commissioner to the country.

Sarva Jeyapalan, 25, who was born in Sri Lanka and has lived in Canada since he was three, also vowed to keep protesting until Canada takes action. She said it's troubling that Harper has not publicly addressed the situation.

"Hamilton's trying to get a hockey team, and our prime minister from Europe makes a statement on that. But thousands of people continue to die daily, and our prime minister hasn't said a single statement," said Jeyapalan, referring a bid to move the Phoenix Coyotes, a NHL team, to the southern Ontario city.

Ghormy Theva, a spokeswoman for a demonstration Monday at the Ontario legislature, said it's hard to say what sort of action Tamil-Canadians and their supporters will take, but they're not giving up their fight.

"If the Tamil community doesn't see affirmative and decisive action taken by the Canadian government in regards to the Sri Lankan issue, you can definitely expect more protesting. Of what sort, what kind, of what outcome, I really couldn't tell you," said Theva, 21.

Some 75 Tamil protesters gathered on the front lawn of the legislature, which is exactly the place Ontario Premier Dalton McGuinty said they should take their concerns rather than blocking city streets.

The protesters, flying both Tamil Eelam and Canadian flags, chanted for Harper and U.S. President Barack Obama to take action to stop the fighting in Sri Lanka.

Other Tamil protesters gathered outside the Sri Lankan consulate in Toronto, and police blocked off a section of University Avenue, just south of the legislature, in an apparent bid to prevent another protest from forming outside the U.S. Consulate.

A series of Tamil protests had closed the busy downtown thoroughfare for more than three days in late April.

Three people were arrested during the highway protest Sunday and the charges against them include assault on a peace officer.

The expressway was fully opened for the morning rush hour.

Toronto is frequently at the centre of the Canadian Tamil demonstrations. Some 200,000 Sri Lankan Canadians live in the area -- one of the largest Tamil populations outside the country.