A former victor of the Tour de France was arrested in Frankfurt for allegedly beating and attempting to strangle an escort in his hotel suite.
Officials say the woman suffered injuries in the attack and Ullrich could be charged with assault or attempted murder. "This will be a fresh start", Mr Ullrich told Germany's Bild newspaper at his villa in Mallorca shortly before flying back to Germany by private plane.
He said he was receiving therapy for problems with drugs and alcohol. She alerted the hotel staff and they called police.
A police spokesperson said the retired German cyclist was arrested after police were called to the hotel, where Ullrich was said to be under the influence of drugs and alcohol.
The neighbour was revealed to be German actor and director Til Schweiger, who starred in Quentin Tarrantino's Inglourious Basterds.
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The Gunners have not won the Premier League title since 2004 and they ended up in sixth place and without a trophy last term. Since his debut in the big 5 European leagues in August 2009, only eight players have scored more than the Gabonese forward.
But he then got into a quarrel with the "escort lady" and "physically attacked and injured her", police said.
Schweiger told Bild that Ullrich 'had nearly become a family member but when his wife left him he started taking amphetamines: he would only sleep for two hours.
Former German cyclist and Tour de France victor Jan Ullrich addresses the media in the northern Swiss town of Weinfelden, Switzerland, July 21, 2015. He also told me that he had a prescription for cocaine'.
But he was then embroiled in doping allegations and excluded from the 2006 Tour de France over his links to the Operation Puerto scandal that centred on disgraced doctor Eufemiano Fuentes, who gave performance-enhancing blood transfusions to top cyclists.
In 2013, he admitted to doping, having been served a two-year ban by sporting regulators.