Oregon City, Oregon -- UFC middleweight Chris Leben turned himself over to authorities yesterday, after violating the terms of his probation stemming from a DUI arrest in 2005. A Clackamas Circuit Court judge had issued a bench warrant for Leben, 27, after he did not complete certain requirements of his probation before moving to Hawaii in 2007.

The exact details of the violation were not known, but one official at Clackamas County Community Corrections speculated it may have been due to unpaid fees or missed classes.

"He came in yesterday afternoon," said Detective Jim Strovink of the Clackamas County Sheriff's Office. "He knew he had violated his [probation] and he admirably turned himself in."

Leben is being held without bail. His next hearing is 9 a.m. on May 8th at Clackamas County Circuit Court, just south of Portland, Oregon.

Leben rose to national prominence during the first season of "The Ultimate Fighter" reality show. He began his UFC career on a six-fight win streak before losing to current champion Anderson Silva. He began his MMA career fighting out of Team Quest in Portland, Oregon, but moved to Oahu, Hawaii, in 2007 to train and teach at Icon Fitness.

By turning himself over to authorities, Leben may have eased the process of securing a visa so he can travel to fight Michael Bisping in London at UFC 85 on June 7th.

"When Chris moved to Hawaii, he was in the process of completing classes for his probation on an old DUI in Portland, Oregon," wrote Icon promoter T.Jay Thompson, "We worked hard to get his probation transferred to Hawaii but were unsuccessful. When he got the call to fight Bisping on June 7th in London, he knew what he had to do."

Thompson added that Leben is in "excellent shape" and plans on concluding his training camp with the help of Matt Hume.