A court in northwest China has sentenced two men to death and three others to prison terms over a clash, which saw 15 people killed in the traditionally Muslim Xinjiang Uighur autonomous region, Chinese state media has reported.

The violence on April 23 in Selibuya township was one of a series of incidents that points to continuing tensions between authorities and members of the region's native Turkic Uighur ethnic minority who are culturally, linguistically and religiously distinct from the Chinese Han majority.

The Xinhua News Agency and other outlets said the alleged leader of an extremist group Musa Hesen was sentenced to death following a one-day trial in the city of Kashgar on Monday for murder, forming and leading a “terrorist” organisation and illegally manufacturing explosives.

Another defendant, Rehman Hupur, also received the death sentence for murder and belonging to a "terrorist" organisation.

The sentences imposed on the three others ranged from nine years to life in prison.

The reports said the defendants did not contest the charges and had lawyers present during their trial. Death sentences in China are automatically reviewed by the country's highest court before being carried out.

A total of 19 members of the group were arrested, and more trials are expected.

Illegal preaching

Authorities said the group regularly watched video clips advocating "religious extremism and terrorism" and attended illegal preaching ceremonies, and had planned to carry out a major attack in densely populated areas of Kashgar in the summer.

The deadly clash erupted after local police and community workers discovered suspicious behavior at a home in Selubiya outside of Kashgar.

Fearing his group's discovery, Hesen then led other members in hacking and burning to death 15 members of the security services, while six of their own were shot to death at the scene.

The death toll was the highest for a single incident in months in northwestern China's Xinjiang Uighur autonomous region, where recurring violence pits Uighurs against the authorities and majority ethnic Han Chinese migrants.

Beijing says China faces an "organised terrorist threat from radical Muslim groups" in the region.

Xinjiang, a sprawling region that borders Central Asia, Afghanistan and Pakistan, is home to millions of Uighurs, many of whom complain of tight restrictions on religious and cultural life by Beijing and say they have been marginalised by policies favouring Han migrants.

Chinese government says it treats minorities fairly and spends billions of dollars on improving living standards in minority areas.