A man turned up at a police station in Andernach with a hand grenade wrapped in a cloth.
The 62-year-old said he found the grenade while walking on the Rhine, as the police announced on Thursday.
Because the officials could not rule out that the grenade was still armed, they instructed the 62-year-old on Wednesday to put it down in front of the door.
The ordnance disposal service finally gave the all-clear.
According to their own statements, the police initiated criminal proceedings against the finder.
"Carrying a hand grenade in public" is a criminal offense, said a spokesman.
The man's behavior is probably a violation of the War Weapons Control Act.
The 62-year-old should not have picked up the grenade, but should have called the police directly.
Icon: The mirror
wit / dpa