A gunman opened fire and set a blaze inside a Mormon church in the small town of Grand Blanc, Michigan, on Sunday, killing four people and injuring at least eight others, authorities said.
Police said the 40-year-old suspect rammed the church's front door with a vehicle before opening fire while hundreds of worshippers were gathered for a service of the Church of Jesus Christ of Latter-day Saints. He was killed in an exchange of gunfire with officers.
The blaze, which investigators believe was deliberately set using an accelerant, engulfed the building but has since been extinguished. Officials said several suspected explosive devices were also found, but gave no details on their potential use.
Two of the victims died of gunshot wounds; authorities did not immediately specify how the other two were killed. As many as seven people were unaccounted for in the chaotic hours that followed the attack.
The FBI has taken over the investigation. No motive has been identified and it remains unclear whether the attacker had any connection to the church or its congregation.
"This appears to be yet another targeted attack on Christians in the United States of America," U.S. President Donald Trump commented on his platform Truth Social. "The suspect is dead, but there is still a lot to learn."
The attack comes just weeks after a shooting during a school church service in Minneapolis, Minnesota, in August. A person fired through the windows of a church, killing two children aged 8 and 10 and injuring several others.