Sharjah24 - AFP: Gunmen with explosives stormed a Catholic church and opened fire in southwest Nigeria on Sunday, killing "many" worshippers and wounding others, the government and police said.

The violence at St. Francis Catholic Church in Owo town in Ondo State erupted during the morning service in a rare attack in the southwest of Nigeria, where jihadists and criminal gangs operate in other regions.

Pope Francis said in a statement he had learned of the "death of dozens of faithful", many children, during the celebration of the Christian holiday of the Pentecost.

"While the details of the incident are being clarified, Pope Francis prays for the victims and for the country," he said.

No group claimed responsibility for the attack.

The motives and the exact death toll were not immediately clear, but President Muhammadu Buhari condemned the "heinous killing of worshippers".

State police spokeswoman Ibukun Odunlami said the gunmen also attacked the church with explosives, leaving an unknown number of worshippers dead.

A spokesman for the Ondo State governor's office said they would not be giving an official casualty figure for the moment.

But a witness, who gave his name as Abayomi, told AFP at least 20 worshippers had died in the attack.

"I was passing through the area when I heard a loud explosion and gunshots inside the church," he said.

He said he saw at least five gunmen on the church premises before he ran for safety.