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.

Leon Wang, president of AstraZeneca China, "has been detained", a representative of the firm's global media team said in an email to AFP.

"If requested, we will fully cooperate with the Chinese authorities," they said.

"We continue to deliver our life changing medicines to patients in China and our operations are ongoing," they said.

Last month, the firm confirmed that Wang had been placed under investigation.

China is a key market for AstraZeneca, developer of a Covid-19 jab widely administered throughout the world during the coronavirus pandemic.

But in September, the firm confirmed several employees were under investigation in China after a report said they were being questioned about potentially illegal data collection and drug imports.

The probes involved five current and former employees of the firm -- all with Chinese citizenship -- and were being led by authorities in the southern city of Shenzhen, Bloomberg said.

One investigation related to the firm's collection of patient data, which authorities suspect may have breached Chinese privacy laws, Bloomberg reported, citing people with knowledge of the situation.

Another probe related to imports of a liver cancer drug that had not been approved in mainland China, according to Bloomberg.

The firm, headquartered in the United Kingdom, has 90,000 employees globally.

Global firms have faced an increasingly difficult business environment in China in recent years, industry groups say, citing a lack of transparency on data laws and prolonged detentions of employees in the country.