Authorities are investigating the chairman of China Southern Airlines, the country's biggest carrier, for "severe violations of discipline", according to an official statement, using a phrase which typically refers to corruption.

The Central Commission for Discipline Inspection, the Communist Party's corruption watchdog, gave no details of the case involving Si Xianmin in a brief statement posted on its website late Wednesday.

Si was also president and deputy Communist party chief of the state-owned airline's parent company. He has spent most of his 40-year aviation industry career at China Southern, his official biography showed.

China Southern stock was down 0.32 percent in Hong Kong but rose 2.13 percent in Shanghai in morning trade on Thursday.

The airline, one of China's "Big Three" carriers and the largest by fleet size, recorded a 48.4 percent year-on-year fall in net profit to 1.17 billion yuan ($186 million) in the third quarter, according to an earnings report.

The listed unit confirmed the investigation, saying it continued to operate in the "usual and ordinary" course of business, according to a statement.

Since President Xi Jinping took office more than two years ago, China has launched an unprecedented anti-corruption campaign, which has brought down government officials and corporate executives.

On Monday, the anti-graft agency said the second-highest-ranking executive of auto giant Dongfeng Motor Corp. was under investigation for violations of discipline.

Last month, authorities said they were investigating the former boss of state-run energy giant Sinopec for alleged corruption -- the latest of several senior oil sector figures to be probed.