The rival version of events on November 9 has cast doubt on the official history of one of the most celebrated decisions of the century, as Berliners prepare to mark the 20th anniversary of the breaching of the wall with a "Festival of Freedom" this weekend.

Until recent weeks, Harald Jaeger, a Stasi officer at Bornholmer Strasse in north Berlin, held the undisputed mantle of the man who peacefully breached the Berlin Wall. But now Heinz Schafer, who was a colonel in the East German army in 1989, has declared that he was the first to open the barriers, at Waltersdorf in the far south of the city. Col Schafer, a 78 year-old who lives in a bleak suburb not far from the former crossing, only put forward his account in a talk to schoolgirls earlier this year.

"As soon as I saw the announcement on television [that travel restrictions for East Germans had been lifted], I put on my uniform and returned to the station," he said. "People had already gathered between the fence and the barrier and were demanding the right to cross. I had certain things to do – for example, we had to take the ammunition out of the self-shooting guns to make them safe...