The German Olympic Sports Confederation (DOSB) identified Sachenbacher-Stehle early Friday afternoon, following a morning of speculation.
The International Olympic Committee IOC informed the German DOSB that a routine drugs test had come back “showing anomalous results,” at at 9.30pm on Thursday night, a statement said.
A secondary doping probe was launched by the IOC disciplinary commission and a hearing scheduled for Friday. The head of the DOSB will then announce its results.
"I don't want to say any more about it yet," said chief de mission Michael Vesper.
"The announcement could come this afternoon or early evening," said Vesper. Sachenbacher-Stehle was on Friday afternoon yet to comment on the revelation.
As yet there is no indication as to whether the anomalous result could have been due to medication the athlete was taking rather than deliberate doping.
Sachenbacher-Stehle switched over to biathalon two years ago, after formerly competing in cross-country skiing.