The FBI is still working to determine a motive and has interviewed more than 100 victims and witnesses, said Reuben Coleman, the special agent in charge of the bureau’s Detroit field office.
He said the agency is investigating the incident as an act of targeted violence but declined to say whether authorities believed that target was a person or the Mormon Church.
The gunman, Thomas Jacob Sanford, 40, died after police exchanged gunfire with him, according to law enforcement.
Michigan Governor Gretchen Whitmer (Democrat) condemned the attack and said she spoke with United States President Donald Trump, who shared his condolences.
At the end of a month jarred by several high-profile shootings, she urged against speculation about the gunman’s motive.
“[I] just ask that people lower the temperature of rhetoric,” Whitmer said. “Keep your loved ones close and keep this community close to your hearts.”
James Deir, the special agent in charge of the Detroit division of the Bureau of Alcohol, Tobacco, Firearms and Explosives, said investigators recovered improvised explosive devices during the investigation.
“There is no place in our society for this,” Deir said of the attack. “There’s absolutely no place, but it’s become all too common, and as we know, we have become more and more desensitised.”
White House press secretary Karoline Leavitt told Fox News that the FBI was executing search warrants at residences and family homes of the shooter and that his family is co-operating with the investigation.
Sanford, who police said is from the nearby town of Burton, served in the US Marine Corps between June 2004 and June 2008 and deployed in Operation Iraqi Freedom from August 2007 to March 2008, according to military records.
Sanford’s father declined to comment in a text message to the Washington Post. Efforts to reach other relatives of Sanford were unsuccessful.
McCandlish Road, a peaceful tree-lined street with ranch homes where the church is, was bustling today with reporters, photographers and videographers.
A roadblock guarded by a Grand Blanc Township police officer was set up to prevent the press from getting too close to the church.
Dan Beazley, from the Detroit suburb of Northville, walked down the street towards the remains of the church, dragging an oversize cross.
“I’m here to shine a light on about the darkest situation you can get to,” said Beazley, who said he had taken the cross to Arizona this month for the funeral for conservative activist Charlie Kirk.
“When people are worshipping, I don’t care what religion they are. They should be able to go to worship in peace without worrying about getting killed,” he said. “There should be no safer place.”
Andrew Beauchesne, 27, a clerk at O’Reilly Auto Parts down the road, said he was driving to work yesterday when he saw smoke in the distance.
“Just horrible. You can’t expect it to happen here, but it did,” he said. “It’s kind of crazy.”
Daniel Mallett, an assistant manager at O’Reilly who, like Beauchesne, lives in Grand Blanc, said he was stunned by the attack, which he described as “too close to home”.
“We’re kind of helpless,” he said. “It’s all political to me, the right against the left, about gun control.”
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