A man turned up with a hand grenade wrapped in a cloth at a police station in Andernach.
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 man 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 62-year-old. "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.