While it remains unclear why AstraZeneca China President Leon Wang has been detained, news of his arrest comes just days after it was reported that he was under investigation for alleged medical insurance fraud in the country.

AstraZeneca said on Wednesday its China president Leon Wang had been detained by Chinese authorities and, although it did not know the reason, it did not believe it was linked to a large health insurance fraud case involving the company.

China's investigation of AstraZeneca's top executive in the country is raising questions about the company's tactics there.

The president of AstraZeneca’s China division has been placed under investigation by local police, as Beijing advances an anti-corruption crackdown in the healthcare sector.The British pharmaceutical giant confirmed on Wednesday that Leon Wang,

Pharmaceutical giant AstraZeneca said Thursday that the head of its China operations had been detained, after reports the firm was under investigation for potentially illegal data collection and drug imports.

BMO Capital Markets analyst Etzer Darout in a note to investors said the insurance fraud probe represents a “headline risk” to AstraZeneca, but contends that the share selloff is “overdone” and likely a knee-jerk reaction by investors.

The company believes Chinese authorities are probing allegations that two current and two former employees had illegally imported cancer drugs.

Shares of AstraZeneca dropped more than 7% yesterday after the Chinese publication Yicai Global reported that dozens of senior executives in the company's China subsidiary have been implicated in an insurance fraud case.