SYDNEY, Sept. 8 (AFP) - Two Australian journalists were rushed out of China overnight after Chinese police sought to question them, their employers said on Tuesday (Sep 8).

The withdrawal of Australian Broadcasting Corporation's Bill Birtles and Australian Financial Review correspondent Michael Smith came shortly after China detained a high-profile Australian journalist working for its state-run CGTN TV network.

The ABC said Birtles, who was based in Beijing, and Smith, who worked from Shanghai, had sheltered in Australian diplomatic offices for several days before being allowed to leave the country.

The pair flew out of Shanghai accompanied by Australian diplomats on Monday and arrived in Sydney early Tuesday.

The incident comes amid worsening diplomatic relations between the two governments and followed the detention last month of Cheng Lei, an Australian working as a business news anchor for CGTN.

Chinese authorities have given no reason for Chen's detention.

The ABC said Australia's foreign ministry warned Birtles last week that he should leave China but on the day before his scheduled departure on Thursday seven police officers visited his home at midnight and said he was banned from leaving.

The police said they wanted to question Birtles over a "national security case", prompting him to take refuge at the embassy.

Birtles was questioned by Chinese police later in the week in the presence of Australian diplomats and the travel ban was lifted, ABC said.

The AFR said Smith was also visited by police the same night in Shanghai and that both men were questioned in relation to the case against Cheng.

"This incident targeting two journalists, who were going about their normal reporting duties, is both regrettable and disturbing and is not in the interests of a cooperative relationship between Australia and China," the Financial Review's editor-in-chief Michael Stutchbury and editor Paul Bailey said in a statement.

Australia earlier this year warned its citizens they faced the risk of arbitrary detention in China.

Ties began to sour between Australia and China - its biggest trading partner - more than two years ago when Australian authorities began to move against what was seen as China's growing political interference and influence-peddling in the country.

Beijing was particularly infuriated by Australia's leading role in international calls earlier this year for an investigation into the origins of the coronavirus pandemic, which began in the Chinese city of Wuhan.

Since then, China has taken steps to curb key Australian imports and encouraged Chinese students and tourists to avoid the country.

Cheng is the second high-profile Australian citizen to be detained in Beijing after writer Yang Hengjun was arrested in January 2019 on suspicion of espionage.