Senior Chinese airline and aviation officials misused company funds, took bribes and accepted golf outings as gifts, China's anti-corruption watchdog said in a series of inspection reports of central government agencies and conglomerates.

The Communist Party's official newspaper and its economic planning agency were also singled out by the Central Commission for Discipline Inspection (CCDI) in its latest reports under President Xi Jinping's three-year-old anti-graft drive.

At Commercial Aircraft Corporation of China Comac, the manufacturer of China's C919 airplane, officials were found to have taken unnecessary trips overseas at company expense and used company money to pay for personal expenses, the CCDI said in its reports.

Executives at Aviation Industry Corporation of China AVIC, a shareholder of Comac, accepted bribes or received kickbacks from suppliers, CCDI said. Others took holidays and played golf at company expense.

The CCDI said it also uncovered bribe-taking, at Civil Aviation Administration of China, the industry regulator, as well as at China Eastern Airlines and the parent of Air China.

Comac Chairman Jin Zhuanglong, AVIC Chairman Lin Zuoming and China Eastern Chairman Liu Shaoyong accepted the CCDI findings and pledged to take action, according to the commission's reports.

China Southern Airlines, the first state carrier probed by CCDI earlier this year, has closed overseas bank accounts, taken action against corrupt executives and stopped free rounds of golf courses for premier clients in the wake of CCDI inspection tours.

China Eastern and Air China group could not immediately be reached for comment. An AVIC spokeswoman also declined to comment, but said the company would put out a statement possibly as early as later on Monday. Comac released a statement late on Sunday pledging to rectify the problems.

The CCDI also said it was investigating three officials at the economic planner, the National Development and Reform Commission (NDRC), for suspected corruption. All were suspected of "serious violations of discipline", it said, the usual euphemism used by Chinese officials for corruption.

The NDRC confirmed the investigation and said it was determined to crack down on corruption.

The People's Daily newspaper also came in for criticism, with the watchdog alleging it covered up news in exchange for money and abused government funds.

People's Daily Editor-in-Chief Yang Zhenwu was quoted in the commission's statement as saying the paper would step up its vigilance against graft. The paper could not immediately be reached for comment.

The graft-buster's reports come as the government rolls out new guidelines to overhaul China's inefficient state sector. Beijing has targeted 26 major state-owned firms for inspections this year.