Drug-fuelled bodybuilder parties for hours on Merkel’s jet...in only his underpants

German police are investigating how a half-naked, drug-fuelled bodybuilder was able to party for hours on board an empty government jet used by German Chancellor Angela Merkel.

Wearing only underpants and high on drugs, he danced on a wing, sprayed foam around, and pushed cockpit buttons, causing €100,000 worth of damage.

The incident took place on July 25, when the 24-year-old man, clutching a bag full of ecstasy pills and marijuana, boarded the empty jet while it was parked at a closed military section of the Cologne airport.

The Turkish bodybuilder named as Volkan T proceeded to stage a raucous, one-man party. Reports in the German newspaper Der Spiegel said he stripped down to his underpants, sprayed fire extinguisher foam around the interior, pushed buttons in the cockpit, released an inflatable emergency slide, and danced on the wing of the Airbus 319.

The incident was initially reported last month, but is now attracting renewed attention after an intriguing eight-page police report was leaked to newspapers.

According to newspapers including Welt am Sonntag and General-Anzeiger, the report reveals that the plane was accessed through its emergency exits and the cockpit door was open.

It also says it took police, security guards, and members of the army almost four hours to get the intruder off the plane.

It was also reported that the Airbus was loaded with up to eight tonnes of fuel and, technically, the intruder could have taken off or at least got it rolling.

The Cologne state prosecutor’s office would not comments on the contents of the police report.

“The investigation is focused on the charges of dangerous interference in aviation but also trespassing and damage to property,” prosecutor Ulrich Bremer told Der Spiegel.

However, he ruled out terrorism as a motivation.

On the night in question, Volkan T reportedly had a row with his girlfriend. He drove from his home in Cologne to the airport and got past a guard post by saying he had been invited to a wedding reception being held in the nearby officers’ quarters.

He climbed a barbed wire fence, clambered onto the plane’s left wing and got in through an open emergency exit.

While playing with the cockpit buttons, he inadvertently triggered an alarm that was logged by military personnel at 8:40pm. However, he was not arrested until 12:23am, when a police dog bit him in the leg.

Volkan T was arrested and is being detained in a secure psychiatric hospital.