WAYNE, Mich. (AP) — A Michigan police chief said church staff shot and killed a man armed with a handgun and a long gun, averting a potential mass shooting at a church west of Detroit on Sunday morning.

Chief Ryan Strong said parishioners at CrossPointe Community Church in Wayne spotted the gunman driving recklessly and then saw him exit his vehicle wearing a tactical vest and carrying weapons. The man began firing as he approached the building and was confronted, Strong said at an evening news conference.

“A parishioner struck the gunman with his vehicle as the gunman shot the vehicle repeatedly,” Strong said. “At least two staff members shot the gunman, causing the fatal wounds.”

Strong said the gunman’s motive remains unclear, but it appears he was suffering from a mental health crisis.

The shooting happened around 11 a.m. at CrossPointe Community Church in Wayne, a city of about 17,000 people some 25 miles (40 kilometers) west of Detroit, the church’s pastor, Bobby Kelly Jr., told the Detroit News.

Police said one person was shot in the leg.

Kelly said a church member ran the suspect over with his truck, giving the security guard time to shoot him. Police described the suspect as a 31-year-old white male.

The person who was shot in the leg was the security guard, the pastor told the newspaper. No one else was hurt, he said.

About 150 people were attending the service, Kelly said.

Worshipper Wendy Bodin said she heard a loud “boom” and when she looked outside she saw a man sprawled out on the grass in front of the church. “I thought he got hit or crashed his car or was hurt,” Bodin told WXYZ-TV. “And another lady saw and pointed to me and said ‘oh my, call 911!’”

Wayne Police Deputy Chief Finley Carter III said it was too early to know why the church was attacked. FBI Deputy Director Dan Bongino tweeted the bureau’s “leadership and support teams” were at the scene and helping with the investigation.

Messages left by The Associated Press on Sunday on voicemail and a Facebook page for the church were not immediately returned.

This story has been updated to correct the capitalization of CrossePointe.