GRAND BLANC, Mich. — A gunman drove his truck into a Michigan church where hundreds were worshiping on Sunday morning, shooting congregants before setting the building on fire, officials said.

At least four people were killed and eight others were injured in the shooting and fire, according to police. The gunman was then killed in a shootout with responding police.

The FBI is now leading the investigation, calling the attack an “act of targeted violence.”

The mass shooting comes amid a rash of violence against churches and other religious institutions and amid a series of politically motivated shootings. It also comes after a mass shooting at a waterfront bar in North Carolina left three people killed late Saturday night.

The shooting on Sunday morning was at The Church of Jesus Christ of Latter-day Saints in Grand Blanc, Michigan.

The fire set in the aftermath of the shooting grew to a five-alarm blaze that caused a partial collapse of the structure, according to law enforcement officials. James Deir, Special Agent in Charge of the ATF Detroit Field Division, said during a press conference Sunday night that the gunman used gasoline as an accelerant to burn the building.

Officials said that the chapel is a “total loss” as investigators work to comb through the rubble.

Michigan State Police said that after the shooting, they responded to several bomb threats at other locations in the area — some of them churches.

Officials confirmed that of those shot, one victim died at the scene, another later died at the hospital and two more individuals were found dead at the scene due to the fire. Eight others remain hospitalized, seven are in stable condition and one is in critical condition.

The gunman was identified by police as 40-year-old Thomas Jacob Sanford.

The church was deliberately set on fire by the suspect, who officials said is from Burton, Michigan, about 8 miles north of Grand Blanc.

“We do believe we will find additional victims once we have that scene secured,” Renye said.

The attack unfolded at 10:25 a.m. and “hundreds of people” were attending the service, according to Renye.

“He ran the vehicle through the front door, exited and started firing shots,” Renye said of the suspect, adding that it remains unclear what connection, if any, the suspect had to the church.

A source briefed on the investigation told ABC News that detectives are urgently working to determine the motive behind the shooting. Investigators are working to learn whether the church had been the target of threats in recent months and looking to see whether the timing could be connected to the death on Saturday of Russell M. Nelson, president of The Church of Jesus Christ of Latter-day Saints. He was 101 years old.

Nelson died at his home in Salt Lake City, church spokesperson Candice Madsen said in a statement.

President Donald Trump said he’s been briefed on the shooting and fire, writing Sunday on social media, “This appears to be yet another targeted attack on Christians in the United States of America.”

“The Trump Administration will keep the Public posted, as we always do. In the meantime, PRAY for the victims, and their families. THIS EPIDEMIC OF VIOLENCE IN OUR COUNTRY MUST END, IMMEDIATELY!” Trump said.

Trump also wrote that the FBI is leading the investigation efforts. Trump said that while the suspect is dead, there is “still a lot to learn.”

Vice President JD Vance posted his own statement on social media, calling the shooting and fire at an LDS church “awful.” He said the “entire” Trump administration is monitoring the incident.

“Just an awful situation in Michigan. FBI is on the scene and the entire administration is monitoring things. Say a prayer for the victims and first responders,” Vance wrote.

Shortly after the shooting, Attorney General Pam Bondi said in a post on X, “I am receiving briefings about what appears to be a horrific shooting and fire at an LDS church in Grand Blanc, Michigan. @FBI and @ATFHQ agents are en route to the scene now. Such violence at a place of worship is heartbreaking and chilling. Please join me in praying for the victims of this terrible tragedy.”

Michigan Gov. Gretchen Whitmer said her “heart is breaking for the Grand Blanc community” in a statement on X.

“Violence anywhere, especially in a place of worship, is unacceptable,” she said. “I am grateful to the first responders who took action quickly. We will continue to monitor this situation and hold the Church of Jesus Christ of Latter-Day Saints in the Grand Blanc close.”

Renye said during Sunday’s news conference that the FBI has assigned more than 100 agents to help in the investigation.

“Violence in a place of worship is a cowardly and criminal act. Our prayers are with the victims and their families during this terrible tragedy,” FBI Director Kash Patel said in a social media post.

Church of Jesus Christ of Latter-day Saints spokesperson Doug Anderson issued a statement confirming that the gunman opened fire on the congregation during Sunday worship services.

“The Church is in communication with local law enforcement as the investigation continues and as we receive updates on the condition of those affected,” Anderson said. “We offer thanks to the emergency responders who are assisting victims and families. We are deeply grateful for the outpouring of prayers and concern from so many people around the world. In moments of sorrow and uncertainty, we find strength and comfort through our faith in Jesus Christ. Places of worship are meant to be sanctuaries of peacemaking, prayer and connection. We pray for peace and healing for all involved.”

For years, law enforcement and homeland security experts have been warning that religious institutions across the board are being targeted for acts of violence.

“We can all agree that our houses of worship should be safe places for people to exercise their freedom of religion but right now we are increasingly seeing them being targets for violence — and not just attacks on any one faith,” Michael Masters, who oversees security operations for the main U.S. network of Jewish schools and synagogues, told ABC News. “Attacks against religious institutions are attacks against our democracy as a whole.”

Masters said there has been an increase in targeted attacks across the faith-based community over the past several years.

“This is something we’ve been working to prepare for in the Jewish community for many years. In the current threat environment, the offenders are often not distinguishing. There’s the Jewish community, the Sikh community, the Annunciation church and now the LDS church in Michigan,” he said.