Police in Quebec have made an arrest amid a spike in Islamophobic hate speech after a massacre inside a mosque in the province's capital.

Despite calls for calm from the province's political leaders, Montreal police received 29 reports of hate incidents in the three days following the attack. In one case, a 45-year-old man from suburban Montreal was arrested.

"They were heated comments on social media concerning Muslims," said Constable Raphael Bergeron of the Montreal police, as the man was charged with uttering threats online and inciting hatred.

Story continues below advertisement

In Sunday's attack on the Centre culturel islamique de Québec, a lone gunman shot six Muslims dead and injured 19 others during an evening prayer.

Allegedly perpetrated by a lone white gunman from Quebec, the massacre is now provoking soul-searching in the province regarding its obsession with the place of Islam in society.

While the wider public is expressing sympathy and solidarity with the victims, there has also been disturbing undercurrent of hateful chatter directed at the victimized community.

"In the past 72 hours we've had more than 15 calls about Islamophobia and six about the extreme right. That's a lot for us," Herman Deparice-Okomba, the head of Montreal's anti-radicalization centre, said.

Also: 'I won't be scared of praying here': Quebec City mosque reopens for worship

Read more: Canadians open wallets for victims of Quebec City mosque massacre

Read more: Campus support for Muslim students prompts talk about Islamophobia

Story continues below advertisement

Such reactions may illustrate a phenomenon that some security researchers call "reciprocal radicalization."

Since the Sept. 11, 2001, al-Qaeda attacks in the United States, public discussion about how to deal with the threat posed by jihadist groups has frequently gone off the rails into broad conversations about how the West should treat Muslims in general.

Scattered far-right groups often seize upon such discussions, experts say, painting themselves as protectors. At times, such networks can inspire individuals who lash out violently. And because such attacks are sporadic, no one knows how to prevent them.

"The government is relying on rhetoric about multiculturalism and appealing to the better angels of Canadians to deal with this threat," says James Ellis, of the Canadian Network for Research on Terrorism, Security and Society.

But much more needs to be done to understand the problem and counter the threat, he says. "It's a significant issue that requires police, intelligence and policy."

Counterterrorism officials frequently say they are consumed with trying to keep up with jihadist threats, and that these investigations consume most of their resources.

Story continues below advertisement

In 2011, the Canadian Security Intelligence Service released a report that stated that "right-wing extremism has not been as significant a problem in Canada in recent years. Those who hold such extremist views have tended to be isolated and ineffective figures."

Yet hate crimes against Muslims appear to be on the rise in Canada. Cases reported to police stood at 64 in 2013. But they rose to 99 in 2014, according to Statistics Canada.

Within Quebec, this number jumped from 20 to 35 in the same period – about one third of the national incidents.

The Quebec City shooting suspect, Alexandre Bissonnette, 27, is the sole suspect in the mosque massacre. He faces murder and attempted murder charges, but detectives are trying to find evidence to support terrorism charges. The problem for police is that while Mr. Bissonnette is being described as a frequent anti-immigration "troll" on the Internet sites, he is not known to have have any specific motives for the shooting.

Sometimes the motives for such shootings remain mysteries for years. In 2012, Richard Henry Bain shot and killed a bystander at a Parti Québécois rally in Montreal, firing with the intention of assassinating then Parti Québécois leader Pauline Marois. His stated hope was his shooting would somehow advance the rights of English speakers in Quebec.

Such violent extremism is not limited to Quebec. In 2014, Justin Bourque shot five Mounties in Moncton, killing three of them, because he saw police as symbols of a corrupt Canadian government.

Story continues below advertisement

In Montreal, Police Chief Philippe Pichet, whose force launched a hate-crime unit last year, is warning that his officers are watching the uptick in racist rhetoric. "It's intolerable to see this happening in 2017 in a place like multiethnic Montreal," he told reporters.

Despite such warnings, Mr. Deparice-Okomba says he is contending with calls about a long list of far-right groups whose members may be asserting themselves in the wake of the shooting, as he works to understand the roots of radicalization at his Montreal centre.

"Some people have a real problem with living together, and the groups denouncing integration are largely based outside Montreal," he said. "We're talking about La Meute, Pegida Quebec, Soldiers of Odin, the Federation of Québécois de Souche, Atalante Quebec …

"A lot of those groups have an Islamophobic discourse fed by hate speech," he added.

"… They reject living together. If we do nothing, it's going to get dangerous."