During the clean-up work in Erftstadt-Blessem in North Rhine-Westphalia, which was badly affected by the flood, a helper found several thousand rounds of ammunition in a full basement.

As the police announced on Monday, the volunteer also found training hand grenades while pumping out the basement on Friday and reported this to the federal police.

A defuser from the State Criminal Police Office then took care of the finds.

The homeowner voluntarily handed over other weapons to the officials, including two rifles, a pistol, a saber and a bayonet.

A complaint was filed against him.

The Cologne police had already announced on Friday that partially loaded weapons were repeatedly found during clean-up work in the Euskirchen district and in the Rhein-Sieg district.

"Parents are urged to make children aware of the dangers," the police wrote on their Facebook page.

Anyone who finds weapons or ammunition should dial the emergency number immediately.