ZARAGOZA, Philippines — Philippine police say two gunmen killed a Roman Catholic priest as he prepared to celebrate Mass at the altar of a chapel in a northern town, in the country’s latest deadly attack on a priest.

Police officials say two men shot Father Richmond Nilo with pistols Sunday night in the chapel in Zaragoza town in Nueva Ecija province. The gunmen, who fired the shots through the chapel window, fled on a motorcycle.

The Catholic Bishops’ Conference of the Philippines said Nilo was the third Catholic priest to be killed in the country in recent months and condemned the “outrageously evil act.”

RELATED: Philippines cardinal condemns shooting death of priest who had just celebrated Mass

“We make our appeal once again to the police authorities to act swiftly in the investigation and to go after the perpetrators of this heinous crime and bring them to justice,” the statement said.

Police created a special force to investigate the killing and were attempting to determine the motive.

Bishop Sofronio Bancud of the diocese of Cabanatuan said the death of Nilo was “an irreparable loss” for the diocese.

“We condemn in the strongest possible terms and deeply mourn the brutal murder of Father Nilo, and the escalating violence and culture of impunity in the country even against helpless clergymen,” Bancud said, according to CBCPNews, the official news service of the bishops’ conference.

“No priest, and no human being for that matter, deserves to be killed with utter brutality, disrespect and impunity. Every priest, however imperfect, is God’s gift to His Church and we are duty-bound to respect them as ‘ambassadors for Christ’,” he said in a written statement.

“To kill a priest then, for whatever motive or cause, is not only unchristian and inhuman, it is also un-Filipino,” the bishop said.

“We earnestly call on our people to pray for Father Richmond, for peace, healing and security of our communities, and for the clergy and the religious, especially in our diocese,” Bancud added.

Nilo is the third Catholic priest to be murdered in recent months. Father Tito Paez was killed in December, and Father Mark Anthony Ventura was gunned down in April.

Another priest, Father Rey Urmeneta, was shot and wounded on June 6.

Crux staff contributed to this report.