QUEBEC CITY, Canada — The deadly mosque attack in Quebec on Sunday prompted massive grief from the city’s cardinal and pledges to support the victims and their families.

“Whether we are Christians or not, an act of violence such as that experienced at the Great Mosque of Quebec touches us all,” Cardinal Gerald Cyprien Lacroix of Quebec City said Monday from Rome. “Hatred is the darkest expression of our humanity.”

“The people of Quebec have always been recognized as a people who want to live in peace and respect,” he added. “We will respond to these hateful acts through our solidarity and pledge ourselves to continue building a society where social peace and respect for all cultures guide our daily lives.”

Six people were killed and several injured after a gunman opened fire inside the Islamic Cultural Center of Quebec during evening prayers Jan. 29.

One man has been arrested in connection with the attack, Alexandre Bissonnette, who had a history of provocative views and antisocial behavior, the Quebec newspaper La Presse reports. He allegedly had made comments critical of foreigners in the online chat room of a refugee advocacy organization.

Authorities initially sought two suspects, but now say one of them was only a witness, The New York Times reports.

Cardinal Lacroix was in Rome at the time of the attack. He was received by Pope Francis early Jan. 30 and discussed the attack.

“Pope Francis assures us of his prayer and his closeness in these painful moments. By giving me his embrace, I felt that he was pressing the whole population of Quebec to his heart,” the cardinal said. “The Pope accompanies us in prayer at this hour of pain.”

The cardinal offered to the families affected by the shooting “our most sincere condolences and the assurance of our prayer.”

Leaders of the mosque said they did not know the suspect. However, the mosque had faced harassing acts, ranging from hate mail and swastika vandalism to a pig’s head left in front of the building, The New York Times reports.

In response to the attack, Catholic churches have opened for prayer.

Quebec’s Notre-Dame-de-Foy Church was scheduled to host a prayer service Monday evening and a Mass on Tuesday evening.

The diocese encouraged broad participation in a Feb. 4 solidarity gathering at the mosque.

Pope Francis also delivered a message in response to the shooting, voicing his prayers.

“The Holy Father strongly condemns the violence that engenders so much suffering,” Secretary of State Cardinal Pietro Parolin said in a message to Cardinal Lacroix.

The Pope’s condolences were also communicated: The Pope “entrusts to the mercy of God the people who have lost their lives, and he unites himself in prayer to the sorrow of those close to them.”

In his message, the Pope also expressed “his deep sympathy to the wounded and their families and to all those who have contributed to the aid, asking the Lord to bring comfort and consolation to the trial.”

In addition, “imploring God for the gift of mutual respect and peace, he invokes upon the families and the people affected by this tragedy as well as all Quebecois the benefit of the divine blessings.”

The Pontifical Council for Interreligious Dialogue voiced “deep sadness and outrage” at the attack on Muslims gathered in prayer in a place of worship.

“With this senseless act were violated the sanctity of human life and respect due to a community in prayer and a place of worship that welcomes,” the statement continued.

“The Pontifical Council for Interreligious Dialogue strongly condemns this act of unprecedented violence and wishes to submit its full solidarity with the Muslims of Canada, ensuring its fervent prayers for the victims and their families.”