Turkish athlete Asli Cakir Alptekin could lose her gold medal and receive lifetime ban.

Turkey’s Asli Cakir Alptekin, who won the women’s 1,500m gold medal at the London Olympics last summer, has reportedly tested positive for a banned substance.

Both the IAAF, the international governing body for track & field, and the World Anti-Doping Agency have yet to confirm the allegations.

Chinese news agency Xinhua reported the story on Friday, and Runner’s World claims sources in New Zealand said the allegations are true. If Cakir Alptekin did in fact fail a test, she could be banned for life since she was found guilty of taking an illegal substance in 2004.

Cakir Alptekin’s teammate Gamze Bulut finished second to her at both the European Championships and the Olympics last year. She would be the Olympic gold medalist if the doping rumors are true — assuming she ran clean.

Prior to 2012, Cakir Alptekin’s results were not earth-shattering. She failed to qualify for the 1500m final at the 2011 world championships and did not advance out of the heats at the 2008 Beijing Olympics.

Her strong performances in 2012 made many people in the sport suspicious, including Great Britain’s Lisa Dobriskey.

“I’ll probably get into trouble for saying this but I don’t believe I’m competing on a level playing field,” Dobriskey said in London.