Updated

Six suspects arrested in a foiled plane hijack in the far-western Xinjiang region are all Uighur men, Chinese state media reported Saturday, adding to ethnic tension in the region days ahead of the third anniversary of deadly riots.

Xinjiang is home to a large population of minority Uighurs (pronounced WEE'-gurs), but is ruled by China's ethnic majority Hans. There have been clashes between authorities and Uighurs resentful of government controls over their religion and culture.

State media reported that the men arrested Friday tried to hijack a plane headed for the regional capital of Urumqi, but that their efforts were foiled by passengers and flight crew. Four crew members were injured in a tussle with the suspects, China's Civil Aviation Administration said.

The plane carrying 92 passengers and nine crew members safely returned to Hotan city in southern Xinjiang 22 minutes after takeoff, according to operator Tianjin Airlines.

Dilxat Raxit, spokesman for the German-based World Uyghur Congress which campaigns for Uighurs' rights, said it wasn't a hijacking attempt but an in-flight brawl over a seat dispute. "We warn China not to use this incident as another excuse for crackdown," Raxit said in an emailed statement.

Friday's incident occurred just a few days before the anniversary of the July 2009 riots in Urumqi when nearly 200 people were killed in fighting between Han Chinese and Uighurs.

Tensions are already high in Hotan, where authorities raided a religious school and are conducting home searches, according to the Washington-based Uighur American Association.

The state-run Global Times quoted regional government spokeswoman Hou Hanmin as saying that the six arrested men are Uighur. The regional government's news portal Tianshannet also identified the suspects, all of whom have Uighur names.

Local media said the group used a crutch for the hijacking attempt, a detail that has been circulated on China's social media sites by bloggers who say they had friends on the flight.

"They had a long crutch that can be broken into pieces, and the pieces had sharp ends," said a microblogger by the name of Shehuatang. Reached over the phone, she refused to give her name or the name of her friend who she said sat in a window seat in row 15.

"My friend said everyone was stunned at the beginning, and then he shouted, 'Beat them,'" the microblogger said.

Passengers used their belts to tie the hands of the suspects, she said.

Beijing says China faces an organized terrorist threat from radical Muslim groups in the region. State media reports have suggested that Friday's hijacking attempt was a terrorist act.

China has invested heavily to raise living standards in Xinjiang. The development has led to an influx of Han, which has been one source of the tensions there.

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