Rolf Aldag, who rode for Team Telekom and its successor T-Mobile from 1993 to 2005, admitted to taking performance enhancing drugs during his career as a professional cyclist.

At a press conference held in Bonn on Thursday, Aldag said he took EPO among other substances. EPO (the hormone erythropoietin) increases the production of red blood cells thereby allowing an athlete's blood to deliver oxygen to muscles more efficiently.

"I started doping before the Tour de France in 1995, and continued using it," Aldag said.

T-Mobile manager Bob Stapleton said Aldag still had the support and trust of the team, and would stay on as sporting director.

Zabel still active rider

Former T-Mobile cyclist Erik Zabel, who won the green jersey of the best sprinter at the Tour de France six times, was highly emotional as he admitted to using EPO before the Tour de France in 1996.

"I used it as a test and ended it after one week because I had problems with the side-effects," said Zabel, who now rides for Milram.

"Since then, for the past eleven years, I have always denied doping. I lied, and I apologize for this," Zabel said with reddened eyes.

Doping doctors fired

The confessions came a day after the university doctors Andreas Schmid and Lothar Heinrich admitted to EPO blood doping in the mid-1990s at Team Telekom.

"I admit that, upon request, I made doping substances, especially EPO, available to certain riders since mid-1990s," Schmid said in his statement. He said he never gave any drugs to riders without their knowledge.

Heinrich also confirmed that he had been involved in doping. "I took part in doping of riders in the course of my work as a sports doctor," he said.

On Thursday, Freiburg university announced it had fired the two sports doctors and also promised a full investigation into the past 20 years of its sports medicine. The doctors have also been suspended by T-Mobile and now face a criminal investigation.

Breaking the silence

Thursday's admissions are part of a string of confessions by Telekom riders. On Monday, the former Telekom riders Bert Dietz and Christian Henn said they had used EPO during their professional careers.

Dietz, Henn, Aldag and Zabel were support riders for the team when its top cyclists won the Tour de France, Bjarne Riis in 1996 and Jan Ullrich in 1997.

The confessions come after weeks after former Telekom masseur Jef d'Hont spoke of widespread doping on the team, including Ullrich.

Ullrich has protested his innocence, and has also denied involvement in the Spanish doping scandal "Operacion Puerto" which has rocked professional cycling since last year.

T-Mobile dropped Ullrich and fellow rider Oscar Sevilla from the team at the start of the 2006 Tour de France because of the allegations.