LONDON -- British heavyweight boxer Larry Olubamiwo has been suspended for four years after admitting using more than a dozen doping substances.

UK Anti-Doping says Olubamiwo tested positive for the blood-boosting drug EPO on Jan. 30 following a bout with countryman Sam Sexton.

The agency says Olubamiwo later admitted to using 13 banned substances, including human growth hormone and anabolic steroids, over a six-year period.

The 33-year-old fighter is banned from participation in all sports until Feb. 28, 2016. All of his boxing results dating to Jan. 1, 2006, have been annulled.

Olubamiwo had a record of 10-3.

UKAD says it investigated Olubamiwo based on intelligence gleaned from the 2007 U.S. Drug Enforcement Administration probe into drug trafficking called Raw Deal.