CBS Radio News said the victim was a suspect in Sunday's blast at the First Assembly of God Church. The bomb reportedly went off as agents knocked on the man's door.
Jerry Singer, special agent with the federal Bureau of Alcohol, Tobacco and Firearms in Chicago, would not immediately confirm that report.
"We don't have any linkage at this time," he said.
Singer said ATF agents already were on the scene, because they were in town investigating Sunday's blast. The garage was at a home about 3 miles from the church.
There were no other injuries reported in the late-afternoon explosion in a residential area on the city's east side.
"I was out in my back yard, and I heard it," said David Dumas, 43, who lives a half-block away from the blast. "It sounded like three or four of those big firecracker blocks they set off on the Fourth of July."
City police and the FBI refused comment.
The bomb Sunday ripped a 10-by-15-foot hole in the church building, injuring 33 people. There have been no arrests.
That bombing was the second at a Vermilion County church in less than six months. The earlier bombing, Dec. 30 outside the Oakwood United Methodist Church in nearby Oakwood, killed a church volunteer who moved a package containing the bomb. Authorities have said they have not established a link between those bombs.
Charles Paxton, who lives four houses down from Thursday's blast, said he heard the explosion about 4:55 p.m. as he was getting home.
"They won't let me out of the house," he said. "The cops have taped everything off."
Danville, a blue-collar town of about 34,000, is on the east-central edge of Illinois, 120 miles south of Chicago.
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