Gunmen opened fire on worshippers and detonated explosives at a Catholic church in southwestern Nigeria on Sunday, leaving dozens feared dead, state lawmakers said.

Legislator Ogunmolasuyi Oluwole said the attackers targeted the St. Francis Catholic Church in Ondo state just as the worshippers gathered on Pentecost Sunday. Among the dead were many children, he said. Adelegbe Timileyin, who represents the Owo area in Nigeria's lower legislative chamber, said the presiding priest was abducted as well.

"Our hearts are heavy," Ondo Governor Rotimi Akeredolu tweeted Sunday. "Our peace and tranquility have been attacked by the enemies of the people."

Authorities did not immediately release an official death toll. Timileyin said at least 50 people had been killed, though others put the figure higher. Videos appearing to be from the scene of the attack showed church worshippers lying in pools of blood while people around them wailed.

It was not immediately clear who was behind the attack at the church. While much of Nigeria has struggled with security issues, Ondo is widely known as one of Nigeria's most peaceful states. The state, though, has been caught up in a rising violent conflict between farmers and herders.

Nigeria's security forces did not immediately respond to enquiries as to how the attack occurred or if there are any leads about suspects. Owo is about 345 kilometers (215 miles) east of Lagos.

"In the history of Owo, we have never experienced such an ugly incident," said lawmaker Oluwole. "This is too much."