More than 6,000 travellers were stranded at Guangzhou's airport on Tuesday after 50 flights were delayed by an unannounced military air drill in eastern China.
The holdups affected many flights and led to some travellers waiting more than 10 hours or spending the night at the airport, according to the New Express.
Most of the delayed flights from Guangzhou were bound for Shanghai, Nanjing , Qingdao , Dalian and other eastern seaboard cities, and travellers were told the holdups were caused by air-traffic control in eastern China.
The delays also partially paralysed air services in Shanghai, and domestic flight restrictions were still in place yesterday at Baiyun Airport in Guangzhou and Shanghai's Hongqiao Airport.
Most travellers were not informed of the reason for the sudden restrictions, although one traveller in Shanghai who was bound for Kunming said air stewards told passengers after boarding that there was a military drill. The flight waited on the tarmac for two hours before passengers were asked to continue their wait in the terminal.
A Shanghai military expert who refused to be named confirmed that the People's Liberation Army Air Force was conducting a long-range flight training exercise between Nanjing, in Jiangsu province, and Guangzhou.
'The training is taking place in the coastal areas of the East and South China Seas,' he said. 'That's why the air restriction covers the whole south China region.
'The [exercise] would definitely affect civil aviation and pose some danger.'
The PLA has stepped up manoeuvres in the Nanjing Military Command - the military region on the cross-strait front line - since Taiwanese President Chen Shui-bian began seeking a UN seat for the island in the name of Taiwan early this year, an effort that is seen in Beijing as an attempt by Taipei to move towards full independence.
Hongqiao airport operation centre commander Wang Jintao refused to confirm the cause of flight restrictions, but said they would stay in place until today.
The General Administration of Civil Aviation of China could not be reached for comment.