ABUJA. Nigeria — Two infants are among the 22 worshippers killed in an attack on a church in southwestern Nigeria that has shocked the West African nation, an emergency official told The Associated Press on Tuesday.

The dead have been taken to the morgue while about 50 wounded people are still being treated in hospital following the attack at the St. Francis Catholic Church in Owo town in Ondo state, said Kadiri Olanrewaju, head of Nigeria’s National Emergency Management Services in Ondo.

The exact number of those killed is not known as some of the dead were taken away by family members for private burials, said residents.

“It is only those at the hospital morgue that I am giving you, not the ones in the church taken home for burial. I don’t have that record,” Olanrewaju with the emergency relief services said.

Ogunmolasuyi Oluwole and Adelegbe Timileyin, both of whom represent Owo at the state and federal legislative houses, told AP earlier that more than 50 were killed in the attack.

Nigeria, Africa’s most populous country with 206 million people, has grappled for more than a decade with an insurgency in the northeast by the Islamic extremist rebels of Boko Haram and its offshoot, the Islamic State West Africa Province. The country now is confronted by growing insecurity problems as separatists and pirates are blamed for attacks in the country’s south while armed groups frequently launch deadly attacks in the northwest.

Before the church attack, Ondo had been considered one of Nigeria’s most peaceful states. But now Owo, a small town of traders and government workers located 50 kilometers (31 miles) from the state capital of Akure, is reeling from the violence of the church attack.

Schools and public gathering spots remained closed on Tuesday and many residents stayed at home, residents said.

The Ondo Police Command has not made any arrests yet nor have they confirmed the identities of the attackers, said to be at least five in number, a spokeswoman said.

“We can only confirm that explosives were used and we found three undetonated IEDs (improvised explosive devices) at the scene,” police spokeswoman Odunlami Funmilayo told the AP.

The attackers “sneaked into” the church premises, said the police. Some of them were “disguised as congregants while other armed men who had positioned themselves around the church premises from different directions, fired into the church,” the police added.

The attackers opened fire on the worshippers just as the Pentecost Mass was ending, survivors said.

“There was no warning, no threat, this place has been peaceful,” said Sunday Adewale, who works in the palace of the local chief. “They just looked for people’s soft spot when people are relaxed.”