A Michigan man went treasure hunting in a river and caught a WWI grenade - that's still live

Ryan W. Miller | USA TODAY

A man who was magnet fishing in Michigan caught a World War I-era surprise Tuesday: a live grenade.

Joseph Alexander dropped a line in the Grand River in Grand Rapids, looking for magnet objects, when he heard a click, he told WOOD-TV.

The object was stuck in the mud, but he managed to pull up the line to see what was attached.

"I thought it looked like a grenade, but not one I've seen before," he told the station. "We brought it back home, took some pictures of it, posted it online, and we started getting comments that 'it's a grenade, call the police.' So that’s what we did."

It turned out the grenade was live, and the bomb squad came to handle the explosive, he said.

Sgt. John Wittkowski told WOOD-TV the Grand Rapids Police Department was being "extra cautious" with the German Granatenwerfer, a grenade used in WWI, but that given its age, it probably wasn't too dangerous.

The grenade will be stored until it is detonated properly with C-4, Wittkowski told the station.

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Alexander told CNN he hadn't found anything as exciting as a grenade before Tuesday. He magnet fishes as a way to find artifacts and clean up rivers.

"It kind of combines environmentalism and treasure hunting," he told the news outlet.

Wittkowski said the activity has become more popular in the area, and he guessed people throw relatives' war souvenirs into the river to get rid of them.

"I'm not sure how and why this happens, but it does," he told CNN.

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