Anyone who urges others to commit a terror act could face up to five years in prison, under new legislation introduced by the federal government as a response to growing terror concerns here in Canada.

Bill C-51: the Security of Canada Information Sharing Act and the Secure Air Travel Act was tabled Friday.

The Act amends the Criminal Code, the Canadian Security Intelligence Service Act, the Immigration and Refugee Protection Act and other bills in an attempt to crack down on homegrown extremists in the wake of attacks last fall in Ottawa and Quebec.

Under the new laws, anyone who posts a video or blog on the Internet urging others to commit a terrorist act will risk arrest, said Justice Minister Peter MacKay.

"It's promotion and advocacy, and what that is is encouraging others to commit a criminal act or a terrorist act," MacKay told CTV's Power Play, adding that the government stopped short of using the term "glorification" of terror activities to represent a criminal offense.

The bill also gives new powers to Canada's spy agency to interfere with suspected terrorists' activities on Canadian soil.

For example, MacKay said police or CSIS members who learn about a financial transaction intended for a nefarious act could "interrupt" or "disrupt" the transaction. Similarly, when a shipment or stockpile of dangerous material is discovered, police could "misdirect" the delivery to prevent it reaching its destination.

"That's what disrupt means," MacKay told CTV's Power Play. "It's a capability very often used in security to try and interrupt a terrorist act or a criminal act."

The bill also:

gives the Canadian Security Intelligence Service the power to engage in activities such as interfering with bank transactions and travel plans to thwart a terror attack.

gives power to a judge to "order the seizure of terrorist propaganda" or order it deleted from an online source.

extends the period that police can detain a terror suspect without charge, with authorization from a judge from three to seven days.

makes it easier for information related to national security to be shared across federal agencies.

allows for a passenger suspected of travelling overseas to commit a terror offence to be removed from a flight.

The bill also makes it easier for security officials to detain suspects, allowing them to apply to a court if they believe someone "may" commit a terrorist activity. In the past, law enforcement officials had to be sure an act "will" be carried out.

"We looked very closely at this and it is a lower threshold to use 'may' as opposed to 'will.' But it is still based on reasonable grounds to believe, there is still the attorney general oversight, and there will still of course be the necessity to appear before a judge," MacKay said.

The legislation represents the most sweeping changes since new anti-terror laws were tabled in the aftermath of the Sept. 11, 2001 terror attacks.

'Many challenges' predicted

Privacy Lawyer David Fraser predicted there will be "many" challenges to the legislation from those who believe the new measures contravene the Canadian Charter of Rights and Freedoms.

"There are going to be many," Fraser told Power Play. "I don’t think there's any doubt and it has often been my experience that when you try to legislate in the emotional aftermath of a tragedy, as is the case here, or when you're looking at an election just down the road, very often there are things that end up in bills for political reasons that do make the legislation more susceptible to a charter challenge."

Prime Minister Stephen Harper unveiled the legislation during an event in Richmond Hill, Ont., just north of Toronto.

In his remarks, Harper said “it would be a grave mistake” to ignore the threat from “radical jihadis,” whom he referred to as one of the most “dangerous enemies our world has ever faced.”

“Jihadist terrorism is not a future possibility, it is a present reality,” Harper said. “Violent jihadism is not just a danger somewhere else, it seeks to harm us here in Canada, in our cities and in our neighbourhoods.”

Opposition reacts

Opposition leaders were quick to respond to the proposed legislation.

New Democrat Leader Tom Mulcair said it is important for Ottawa to provide the necessary resources to combat terrorism, and said he will be reviewing the legislation to ensure it meets that test.

"There are some things in there that clearly will make it possible to say that we've made a safer country for Canadians," Mulcair said.

"Terrorist threats are real, there are thousands of people who have been killed around the world in recent years as a result of terrorist actions and we've got to make sure that we do two things -- that we keep Canadians safe and that we respect our rights."

Liberal Leader Justin Trudeau said he will also be digging into the details of the legislation.

"Obviously the most important priority for any government is to make sure we're keeping citizens safe and that's the lens that were going to be studying this legislation (through). Obviously we'll have to make sure as we dig into the details of what is in this piece of legislation that there are adequate safeguards and oversights and that's what the Liberal party's been calling for," Trudeau said.

Harper has vowed to strengthen Canada’s anti-terror laws in the wake of two attacks last October. On Oct. 20, Martin Couture-Rouleau, a man known to the RCMP to have jihadist sympathies, ran over and killed Warrant Officer Patrice Vincent in St-Jean-sur-Richelieu, Que. Another soldier was injured in the incident, and Couture-Rouleau was shot dead by police.

Two days later, Michael Zehaf Bibeau shot Cpl. Nathan Cirillo in the back as he stood guard at the National War Memorial before running into Parliament’s Centre Block. He died in a hail of bullets.

Harper said Friday that the measures just unveiled include sufficient oversight.

“Violent jihadism is not a human right,” Harper said on Friday, “it is an act of war.”

Bill C-51