Authorities in China's restive Xinjiang region are offering cash to informants who report on neighbours with excessive facial hair, state media has reported.

Officials in Shaya county issued a notice offering rewards ranging from 50 to more than 50,000 yuan ($8 to $8,000) for a wide array of information including tips on those growing beards, the Global Times said on Thursday.

Xinjiang has been hit by periodic deadly clashes between authorities and members of the mainly Muslim Uighur ethnic minority, among whom beards are a religious and cultural tradition.

China has blamed the violence on separatists with ties to foreign terrorist groups, while rights groups say authorities exaggerate the threat to justify religious and cultural restrictions on Uighurs.

Financial rewards on offer in Shaya also cover information on locals "conducting illegal religious activities", the Global Times said, without giving further details.

Xinjiang authorities have also launched a campaign labelled Project Beauty, which attempts to discourage locals from wearing veils -- a common practice among Uighur women.

Residents of the desert oasis city of Kashgar told AFP that to enter government offices, banks or courts, women had to remove their veils and men must be clean-shaven.

Xinjiang -- which covers a sixth of China's territory -- is a strategically important region which abuts Central Asia and contains significant oil and gas deposits.

Police blamed suspects from the region for crashing a car in Beijing's Tiananmen Square last October, killing two tourists and the three people in the vehicle. The incident led President Xi Jinping to call for a security push.

Ilham Tohti, an outspoken Uighur academic who challenged the government's account of the crash, was arrested on terrorism charges this year, provoking an outcry from the United States and European Union.

Authorities also accused Xinjiang residents of carrying out a stabbing spree in March in the southwestern city of Kunming that left more than 30 people dead.