Montreal, Canada – Canadian human rights activists are demanding answers from their government after a former United Nations special rapporteur who investigated Israeli abuses against Palestinians was interrogated at the Canadian border on “national security” grounds.

Richard Falk, 95, was stopped at Toronto Pearson International Airport on Thursday and questioned for several hours. He said a security official told him that Canada had concerns that he and his wife, fellow legal scholar Hilal Elver, posed “a danger to the national security of Canada”.

The treatment of the couple has sparked anger and calls for an explanation from Ottawa.

“We need answers – and from the highest levels of government,” said Corey Balsam, national coordinator at Independent Jewish Voices-Canada, a group that supports Palestinian rights.

Despite the outcry, Canadian authorities have not publicly addressed the incident. But the office of Minister of Public Safety Gary Anandasangaree, who oversees the Canada Border Services Agency (CBSA), has acknowledged the case in a statement to Al Jazeera, saying he is seeking more information about what happened.

“National security safeguards are an integral part of our immigration and border-management framework and, while we cannot comment on specific cases, we are committed to ensuring that our border screening processes respect due process and international obligations,” Simon Lafortune, a spokesperson for Anandasangaree, told Al Jazeera in an email.

“To that end, Minister Anandasangaree has asked the CBSA to provide more specific details on how this particular incident occurred.”

Falk told Al Jazeera on Saturday that he and Elver were asked about their work on Israel, Gaza and genocide as well as about their participation in an event in Ottawa looking into Canada’s role in Israel’s war on Gaza, which a UN inquiry and numerous rights groups have described as a genocide.

After more than four hours of questioning, the pair – both US citizens – were allowed to enter Canada and take part in the Palestine Tribunal on Canadian Responsibility.

‘Patently ridiculous’

Alex Paterson, senior director of strategy and parliamentary affairs at the advocacy group Canadians for Justice and Peace in the Middle East, called the government’s treatment of the couple “patently ridiculous”.

“I think it just lays bare for everyone the reality that they wanted to hamper the tribunal’s work and try and keep Canadian complicity in Israel’s genocide … in the shadows,” Paterson told Al Jazeera on Monday.

He added that the Canadian government “has been trying to avoid questions of its complicity in arming the genocide, and that’s reason enough to do this”.

Since Israel’s war on Gaza began in October 2023, Canadian human rights advocates have been calling on the government to apply pressure on Israel, a longstanding ally, to end its attacks on the Palestinian enclave.

Those calls for concrete action from Canada have grown as Israel’s military assault and restrictions on aid have killed tens of thousands of people and pushed Gaza into a humanitarian crisis.

Last year, the Canadian government announced it was suspending some weapons export permits to Israel amid the atrocities in the territory.

Prime Minister Mark Carney, who took office in March, also voiced opposition to Israel’s blockade on aid to Gaza and a surge in Israeli military and settler violence in the occupied West Bank.

Meanwhile, along with several allies, Carney’s government recognised an independent Palestinian state in September.

But researchers and human rights advocates said loopholes in Canada’s arms export system have allowed Canadian-made weapons to continue to reach Israel, often via the United States.

They have also urged Canada to do more to stem continued Israeli attacks against Palestinians in Gaza and the West Bank and to support efforts to hold Israel accountable for serious abuses, including at the International Criminal Court.

‘Climate of governmental insecurity’

In his interview with Al Jazeera on Saturday, Falk, who served as UN special rapporteur on human rights in the occupied Palestinian territory from 2008 to 2014, said he believed his interrogation was part of a wider push to silence those who speak the truth about what is happening in Gaza.

“It suggests a climate of governmental insecurity, I think, to try to clamp down on dissident voices,” he said.

Al Jazeera has contacted multiple relevant Canadian government agencies to ask whether Ottawa views the 95 year old as a threat to national security – and if so, why.

A CBSA spokesperson said in an email on Monday that the agency could not comment on specific cases, but stressed that “secondary inspections are part of the cross-border process”.

“It is important to note that travellers referred to secondary inspection are not being ‘detained,’” spokesperson Rebecca Purdy said.

“Foreign nationals seeking entry into Canada can be subjected to a secondary inspection by an officer to determine admissibility to Canada. In some instances, the inspection may take longer due to information being gathered through questioning.”

Global Affairs Canada, the Canadian foreign ministry, has not yet responded to a request for comment from Al Jazeera sent on Saturday.

Balsam of Independent Jewish Voices-Canada said treating someone like Falk as a security threat sends a message that “actually none of us are safe from the suppression of dissent and crackdown on voices that are critical of the Israeli regime“.

“We all deserve an answer and an explanation from the government as to this incident, which casts a chill for all Canadians that are speaking out about human rights in general and Palestine in particular,” he told Al Jazeera.