Chinese authorities have launched an investigation against French drugmaker Sanofi following a news report that accused the company of bribing hundreds of Chinese doctors in 2007.

An unnamed whistleblower told the Guangzhou-based, state-owned 21st Century Business Herald that the French company had paid 503 doctors a total of $274,000 to prescribe Sanofi products, disguising the payments as grants for research programs.

China’s official Xinhua News Agency said on Saturday that the Beijing municipal health bureau was teaming up with disciplinary authorities to look into the research programs and determine whether the payments were actually bribes. Sanofi did not immediately respond to a request for comment.