Four people were killed and eight others wounded Sunday when a gunman opened fire inside the Church of Jesus Christ of Latter-day Saints on S. Saginaw Road in Grand Blanc Township and set the building ablaze in what authorities are calling “an act of targeted violence.”

At least two of the fatalities were the result of gunfire, township Police Chief Bill Renye said. One of the eight injured victims remained in critical condition Monday morning, while seven others were stabilized at Henry Ford Genesys Hospital, according to Chief of Staff Dr. Michael Danic.

The attack began around 10:25 a.m. Sunday when the suspect drove a vehicle into the church, exited with an assault rifle, and began shooting, Renye said. Law enforcement arrived within 30 seconds of the first reports and fatally shot the suspect in the church’s rear parking lot eight minutes later. Officials believe the gunman used gasoline as an accelerant to set the church on fire.

The suspect was identified as Thomas Jacob Sanford, 40, of Burton, Michigan. Sanford was a former Marine who enlisted in 2004 and served as a vehicle recovery operator. His record includes a deployment to Iraq under Operation Iraqi Freedom from August 2007 to March 2008. He achieved the rank of sergeant before leaving the service in June 2008. His military honors include the Marine Corps Good Conduct Medal, Iraq Campaign Medal, Global War on Terrorism Service Medal, Sea Service Deployment Ribbon, and National Defense Service Medal.

Reuben Coleman, acting special agent in charge of the FBI’s Detroit field office, confirmed the incident is being investigated as targeted violence. “This act of violence has no place in our state or anywhere else in our country,” Coleman said, noting that more than 100 witnesses had already been interviewed.

The Bureau of Alcohol, Tobacco, Firearms and Explosives reported finding “suspected explosive devices” at the site, though it remains unclear if they contributed to the fire. Renye said the church is considered a “total loss.”

Witnesses described scenes of chaos. Paula Maser, who was attending services, said: “We heard a big bang and it blew the doors in the church, and then everything after that was chaos.” Another local resident, Janet Peera, said she saw “bodies lying on the sidewalk” as emergency vehicles arrived.

As of Monday morning, authorities confirmed all worshippers were accounted for, though recovery crews continued searching debris for additional evidence. None of the victims have yet been publicly identified.