A 27-year-old German man reeled in a French hand grenade from World War II while he was fishing in the northern German town of Emden on Friday, local police said.
The man was fishing on a bridge in Emden when the incident happened, police said. He said he was using "normal fishing tackle with a hook."
"Instead of a pike, it was a grenade," a police spokeswoman said on Saturday.
Police closed off the area around where he was fishing and the device was handed over to the explosive ordnance disposal service.
A similar incident happened in Hamburg where two children fished a World War II hand grenade out of the Alster tributary. The 11-year-olds had attached a magnet to a fishing rod as part of a "treasure hunt."