BUSTED: Jan Ullrich was arrested early Friday for allegedly assaulting a prostitute in Frankfurt. Photo: Arnd Wiegmann/Reuters

Former German cyclist Jan Ullrich was admitted to a psychiatric clinic for compulsory treatment, a police spokeswoman confirmed in Frankfurt on Friday.

The 44-year-old one-time Tour de France winner was detained in Frankfurt on Friday on suspicion of assaulting a female escort. He was initially taken into police custody after allegedly attacking the woman following an argument at a luxury hotel in Frankfurt.

The alleged victim spoke of an incident which occurred while Ullrich was being processed for release.

The German tabloid Bild had initially reported on Ullrich's admission to a psychiatric clinic.