On Pentecost Sunday, gunmen stormed a church in Nigeria. They killed dozens of people, including many children and pregnant women, with explosive devices and machine guns.

A brutal attack on a Catholic church in West African Nigeria has killed as many as 100. Many children and pregnant women were among the dead, said Oluwole Ogunmolasuyi, a local politician in southwest Ondo state, on Monday. Heavily armed perpetrators stormed St. Francis Church in the city of Owo on Whitsunday during a service, shot indiscriminately at the faithful and set off explosives.

“It was barbaric, we’ve never seen anything like it,” Ogunmolasuyi said after visiting the church and a hospital where scores of the injured are being treated. “The number of victims is between 70 and 100,” says Ogunmolasuyi. President Muhammadu Buhari condemned the attack. “This country will never give in to evil and evil people, and darkness will never conquer the light,” Buhari was quoted as saying on Twitter.

Ondo State Governor Rotimi Akeredolu called the attack “heinous and satanic,” adding that “it is a calculated attack on the peace-loving people of Owo.” The exact number of victims and which group is behind the attack remained unclear. Authorities initially spoke of up to 50 dead on Sunday. The government has launched an investigation.

“The attack is undoubtedly terrorist in nature. The scale and brutality suggest it was carefully planned and not impulsive,” said Eric Humphery-Smith, an analyst at security consultancy Verisk-Maplecroft. The attack was motivated by growing ethnic and religious tensions in Africa’s most populous country of about 206 million residents, according to Humphery-Smith.

A video recording was circulated on social media on Sunday, which is said to show the location of the event. Apparently dead people can be seen lying on the ground covered in blood – including children.

Jihadist and criminal groups have carried out numerous attacks on churches in the predominantly Muslim north of Nigeria in recent years. The predominantly Christian south has so far been spared such attacks. Religious conflicts, particularly between Muslims and Christians, are common in Nigeria.