The incident, initially reported last month, attracted renewed attention after an eight-page police report was leaked to German newspapers, Spiegel Online reported Tuesday.
Last month, a 24-year-old man, identified in reports as a Turkish bodybuilder named "Volkan T.," gained access to the aircraft while it was parked at a closed military section of the Cologne airport. High on drugs, he apparently stripped to his underwear, danced on a wing, sprayed fire extinguisher foam inside the cabin and pushed cockpit buttons, police said.
Newspaper accounts indicated the plane was accessible through its emergency exits and the cockpit door was open. Published reports also said the Airbus had up to eight tons of fuel and technically, the intruder could have taken off or at least got the aircraft rolling on the runway.
The Cologne state prosecutor's office, which is investigating the case, did not offer a statement about the contents of the police report Tuesday.
"The investigation is focused on the charges of dangerous interference in aviation but also trespassing and damage to property. As part of that probe it's of interest how the accused got onto the site and into the plane," prosecutor Ulrich Bremer told Spiegel Online.
On July 25, the night of the incident, Volkan T. reportedly had an argument with his girlfriend and is believed to have been high throughout the incident, Spiegel Online said.
The account indicated Volkan T. apparently drove from his Cologne home to the airport and got past a guard by claiming he was going to a wedding reception in the officers' quarters. He climbed a barbed wire fence, walked across the tarmac, climbed onto the plane's left wing and entered the aircraft through an open emergency exit.
While playing with the cockpit buttons, he accidentally triggered an alarm logged by military personnel at 8:40 p.m. local time, the report said. He was arrested about four hours later when a police dog bit him in the leg.
Merkel was at the opening of the annual Wagner opera festival in Bayreuth.
The plane out of commission until this week and damage was estimated at $133,720, Spiegel Online said.