Police discovered the flak cannon, used by the German Wehrmacht in the Second World War, after conducting a search on a family home in the German state of Saxony-Anhalt. The 49-year-old resident was in possession of 200 illegal firearms, one kilogramme of explosives, and 15,000 rounds of ammunition. The anti-aircraft cannon was resting where a car would normally park.
"I thought I'd seen everything, but you can always be surprised," chief investigator Manfred Schmandra told the paper.
The cannon is not in working condition, but Schmandra said this could be easily remedied.
The raid was part of 16 searches in three states, Berlin, Saxony-Anhalt, and Mecklenburg-Vorpommern.
Schmandra told the paper that police were not planning to prosecute most of the weapon owners. "From what we can tell, they are all collectors who got in touch online. But there is still a danger from these weapons. Someone could get a hold of them, or unused ammunition could be dangerous in the case of a house fire," he told Berliner Morgenpost.
Investigations are ongoing.