At least six people were killed in a shooting at a mosque in Quebec City during evening prayers, police said.
Gunmen fired on about 50 people inside the Quebec Islamic Cultural Centre on Sunday at 8pm local time (01:00 GMT).
"Six people are confirmed dead - they range in age from 35 to about 70," Quebec provincial police spokeswoman Christine Coulombe told reporters, adding that eight people were wounded and 39 were unharmed.
Police said two suspects had been arrested, but gave no details about them or what prompted the attack.
The mosque's president, Mohamed Yangui, was not inside the mosque at the time of the shooting. He received frantic calls from worshippers.
He said: "Why is this happening here? This is barbaric."
Speaking to Al Jazeera by phone, he said: "One of the administrators called me and said there was a shooting at the mosque. I am still in shock. I ran to the mosque ... I was told that one attacker was arrested at the scene while another one was arrested nearby."
'A terrorist attack on Muslims'
Canadian Prime Minister Justin Trudeau condemned the shooting as a "terrorist attack on Muslims in a centre of worship and refuge".
"Muslim Canadians are an important part of our national fabric, and these senseless acts have no place in our communities, cities and country," he said in a statement.
The shooting came on the weekend that Trudeau said Canada would welcome refugees, after US President Donald Trump suspended the US refugee programme and temporarily barred citizens from seven Muslim-majority countries from entering the country.
Philippe Couillard, premier of Quebec, said on Twitter that Sunday's attack "is a terrorist act", and called for "solidarity with Quebecers of the Muslim faith".
The mosque leader Yangui added that the centre had not received any threats immediately before the attack.
"The neighbourhood is very peaceful. We have a good relationship with the government, the mayor of Quebec. We have no problem whatsoever," he said.
Writing on its Facebook page after the attack, the centre said: "All of our thoughts are with the children to whom we must announce the death of their father".
The mosque was previously targeted in an Islamophobic attack. In June 2016, during Ramadan, a pig's head was left on the mosque's doorstep along with a note that said "bon appetit". Pork is forbidden in Islam.
"We are not safe here," said Mohammed Oudghiri, who normally attends prayers at the mosque in the middle-class residential area, but did not on Sunday.
Speaking to Reuters, Oudghiri said he had lived in Quebec for 42 years but was now "very worried" and thinking of moving back to Morocco.
OPINION: The death of multiculturalism in Quebec
Basem Boshra, managing editor of the Montreal Gazette, told Al Jazeera that the centre is the city's biggest mosque of six, with some 5,000 members.
"There's a pretty strong Muslim community in Quebec City," he said, adding that there were plans to lower flags at the national assembly as a mark of respect for the victims
Ralph Goodale, Canada's public safety minister, said on Twitter that he was "deeply saddened" by the loss of life and injuries.
Greg Fergus, an MP in Quebec, described on Twitter the attack as "a terrorist act - the result of years of demonizing Muslims".
New York Mayor Bill de Blasio said police were providing additional protection for mosques in that city following the Quebec shooting. "All New Yorkers should be vigilant. If you see something, say something," he tweeted.
Islamophobia in Quebec
Incidents of Islamophobia have increased in Quebec in recent years.
The full-face covering became a big issue in the 2015 Canadian federal election, especially in Quebec, where the majority of the population supported a ban on it at citizenship ceremonies.
Q&A: Quebec minister defends religious ban
In 2013, police investigated an incident in which a mosque in the Saguenay region of the province was splattered with what was believed to be pig blood.
In the neighbouring province of Ontario, a mosque was set on fire in 2015, a day after an attack by gunmen and suicide bombers in Paris.
"It's a sad day for all Quebecers and Canadians to see a terrorist attack happen in peaceful Quebec City," said Mohamed Yacoub, co-chairman of an Islamic community centre in a Montreal suburb. "I hope it's an isolated incident."
Source: Al Jazeera and news agencies