OTTAWA - Six years after devastating terrorist attacks on the United States shocked the world, Public Safety Minister Stockwell Day says Canada is safer than ever before.

"No democratic country in the world today is immune from risk of this kind of terrorism, Canada included," Day acknowledged Friday.

But he added: "Because of the fact that we've put a lot more resources into our safety and security over the last two years, I believe that we are more safe and more secure than we've ever been. But the risks are still there and we have to be understanding of that."

Six years ago Tuesday, terrorists hijacked four airliners. Two were deliberately flown into the World Trade Center in New York, levelling its twin towers. Another plunged into the Pentagon in Washington and a fourth crashed in a field in Pennsylvania after passengers tried to regain control of the aircraft.

Almost 3,000 people, including 24 Canadians, are presumed to have died in the attacks, masterminded by al-Qaida terrorist Osama bin Laden.

Canada responded, in part, by introducing a new Anti-Terrorism Act. However, in the last year, police authorities have lost three tools intended to help them combat terrorism.

Opposition parties banded together to refuse parliamentary approval for renewing two controversial provisions of the act dealing with investigative hearings and preventive arrest. Those controversial measures gave police the power to compel witness testimony and to hold possible terrorist suspects for up to 72 hours without bail.

As well, the Supreme Court of Canada struck down key provisions of the national security certificate process, used to detain suspected terrorists and other potential threats to national security. The court said the process violated the Charter of Rights because detainees were not allowed access to the evidence against them.

Day said Friday that he wants to resurrect all three provisions.

"We want to do everything we can to make sure our country is as safe and secure as possible, at the same time fully respecting and protecting individual rights."

He said the government intends to introduce changes to the security certificate process that will satisfy the court's objections.

"We want to bring those changes in. We want to let parliamentarians take a look at them and hopefully they'll support the changes so that the security certificate process itself can be maintained."

Day said his department is also looking at reintroducing the preventive arrest and investigative hearing provisions of the Anti-terrorism Act. And he urged Liberals, who voted against renewal even though a Liberal government introduced the provisions in the first place, to support the initiative this time.