Acting on a tip about stolen Nazi art, German investigators raided a home near the northern German city of Kiel in 2015. Instead, they discovered an underground garage containing a World War II-era Panther tank, a torpedo, mortars, anti-aircraft guns, more than 1,500 rounds of ammunition and other weapons.

In Germany, weapons of war are strictly regulated under the War Weapons Control Act. The penalty faced by the owner and the future of the tank and other equipment depend on how operational they are — or whether they could be put back into working order.

History of the Panther tank

The development of the Panther tank was fast-tracked after Nazi Germany invaded the Soviet Union in 1941. Despite the surprise attack, Nazi military leaders were impressed by the versatility of the Soviet T34 tank.

The Panther was first put in use in 1943, and was known for its firepower, movement and frontal armor. It was valuable in battle because it had a greater range than other tanks of its day, allowing it to strike first.

Many of the tanks produced were destroyed during the war, and majority of those that remained afterward were scrapped. But Allied powers also made use of some. "There were tanks that were tested by the allies for their strengths and weaknesses," Jan Kindler of the Bundeswehr Military History Museum told DW.

An eccentric buyer

In 1977, a British arms collector discovered a Panther tank in Surrey that was being prepared for the scrapyard. He reached out to German war memorabilia collector Klaus-Dieter F.*, who had it shipped via the Netherlands to the town of Heikendorf.

In the 1980s Klaus-Dieter F. began the process of having the tank restored. "The condition was very desolate," said the man who undertook the restoration in an interview with German radio station NDR 1 Welle Nord, under condition of anonymity. "The sides were cut out and the gun barrel cut off." Pieces taken from another Panther tank were used to repair it.

A local newspaper at the time reported that the restoration cost 500,000 German marks, roughly €255,000 ($303,000), not accounting for inflation. The tank's engine is reported to have been repaired by the Bundeswehr for €28,000.

The tank was not a secret in the man's neighborhood; several German media reports mention that residents saw the owner driving it around town decades ago. "He was chugging around in it during the snow catastrophe in 1978," said Heikendorf Mayor Alexander Orth, in the Süddeutsche Zeitung daily newspaper.

Discovery and removal

After officials discovered the weapons cache, the military was sent in to remove the Panther and other weapons. Twenty men spent nine hours removing the tank from Klaus-Dieter F.'s subterranean garage.

Though the engine of the tank had been restored, it did not have tracks. The Panther was connected to other tanks to pull it out of the garage and move it onto a low-loader trailer.

The images of a World War II-era German tank being pulled out of an underground garage in a leafy German suburb drew international attention as people tried to understand the story behind it. "Some people like steam trains, others like tanks," Orth told USA Today at the time.

An expensive hobby

Now, six years later, the trial has begun. It will determine whether Klaus-Dieter F. broke German law and what should happen to the tank and other weapons.

For many observers, one of the key questions has been why he would spend so much money and time on restoring a Nazi tank. Aged 78 at the time of the confiscation, he seems unlikely to have had any military plans. His lawyer insists that he is not a Nazi sympathizer, and the restoration project is his "life's work."

In court, Klaus-Dieter F. identified his profession simply as "businessman." Neither he nor his lawyer have explained why he pursued such an expensive and unusual hobby. His lawyer has declined to respond to a DW inquiry.

The defense has argued that the mere fact that the tank and other confiscated weapons appear on the list of weapons of war according to the War Weapons Control Act is not enough to establish that the defendant broke any laws. The judge, however, insisted on investigating whether the Panther could be used as a combat weapon in a conflict between armed states. The barrel of the tank's gun is corroded with rust, but an expert said in court it could be cleaned in a few days.

A verdict is expected later this month, with the defendant likely to receive a suspended sentence and a fine. 

The future of the Panther is currently unknown. The defendant's lawyer said a military history museum in the United States was interested in purchasing it, and said his client has acquired a permit for its export.

"There are people in the world who have their own tanks," said military historian Kindler about the global community of tank enthusiasts, but the regulation of such collections "is relatively strict in Germany."

*Editor's note: DW follows the German press code, which stresses the importance of protecting the privacy of suspected criminals or victims and requires us to refrain from revealing full names in such cases

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