NAIROBI, June 17 (Xinhua) -- Eunice Jepkirui Kirwa, who won marathon silver at the Rio Olympics in 2016, has been suspended for four years for doping.

According to Athletics Integrity Unit (AIU), Kirwa, who resides in Kapsabet town, Kenya, had her blood sample turn positive for prohibited blood-booster EPO. Her four-year suspension is backdated to May 7.

"The Athletics Integrity Unit has issued a decision against Bahraini long-distance runner Eunice Kirwa for a violation of the anti-doping rules," the AIU said in a statement on Monday.

So far, the top two women, who won gold and silver from Rio Olympics marathon have both failed anti-doping test.

Kenya's Jemima Sumgong was banned in January for attempting to hinder an investigation into her use of EPO by supplying false documents.

Kirwa, who also won world bronze in Beijing in 2015, can appeal the ban at the Court of Arbitration for Sport.

Former world champion Mare Dibaba of Ethiopia who took bronze in 2:24:30 is now the highest ranked Olympian.

Last week, another Kenyan Felix Kirwa, a former Singapore Marathon silver medalist, was banned for failing an anti-doping test. Felix Kirwa's urine sample test came back positive with the presence of prohibited substance strychnine.

The 23-year-old, who was sixth at the Chongqing Marathon in China back in 2015, will have to serve a nine months' ineligibility from competing in any athletics event starting from Feb. 14.

Three other Kenya runners -- former world 1,500m champion Asbel Kiprop, Hilary Kepkosgei Yego and Samson Mungai Kagia have tested positive to banned substance in 2019.