Kenyan marathon runner Wilson Kipsang has been handed a provisional suspension for alleged anti-doping rule violations, the Athletics Integrity Unit (AIU) announced on Friday.
The former world record holder has been issued with a notice of charge for whereabouts failures and tampering or attempted tampering, the AIU said on its website.
Under World Athletics anti-doping rules, athletes must inform testing authorities of their whereabouts for one hour of every day. Three missed tests and/or filing failures within a 12-month period results in an automatic ban.
Kipsang has triumphed at four of the six major marathons, winning twice in London along with successes in Berlin, New York and Tokyo.
The 37-year-old won the bronze medal at the 2012 Olympics but withdrew from contention for the 2016 Rio Games.