The IOC says a Russian cyclist and Colombian track and field athlete have failed Olympic drug tests.
-London Olympics 2012 - Complete coverage
IOC spokesman Mark Adams says Russian track cyclist Victoria Baranova was expelled after failing a pre-competiton test. Her positive test had been confirmed Friday by cycling's governing body.
Baranova tested positive for testosterone July 24 in Belarus.
Adams says Colombian 400-meter runner Diego Palomeque has been provisionally suspended after a pre-competition positive test. The 18-year-old athlete did not start in his scheduled heat on Saturday.
