At least four persons were killed and eight injured in a knife attack on Thursday in the restive northwestern region of Xinjiang.
In 2009, nearly 200 people were killed in rioting between members of the Muslim Uyghur -- the majority community in the autonomous region -- and Han Chinese communities.
Thursday attacks happened as the Communist Party of China (CPC) chief of Xinjiang, Zhang Chunxian, in Beijing for the ongoing session of the National People's Congress (NPC), said : "Although the situation [in Xinjiang] remains tough, the overall stability in Xinjiang is improving and under control."
Details of the attack of including the ethnicity of the victims have not been revealed by government officials.
Agency reports said one person hacked four people to death and injured eight others before being detained by authorities in the oil industry hub of Korla in the western Xinjiang region.
Quoting local residents, news agency Associated Press described it as a result of a gambling dispute, "…while online accounts characterized it as an attack by an ethnic Muslim Uyghur against members of the country's Han Chinese majority."
Since the 2009 riots, which was China's deadliest ethnic violence in decades, tensions have been high and armed police patrol parts of the streets.
In December, three suspected suicide bombers from the Uyghur community were given death penalties and one was sent to life imprisonment by a court for attempting to hijack and blow up a domestic flight in June last year.
The court said that those sentenced were influenced by "religious extremism" for about five months last year but did not give further details.
Exiled Uyghur groups accuse the Chinese state of trying to crush their culture and subjugate their religion.
But authorities say they are fighting only violent extremists who want to take over the region and form an independent Islamic state.
"A lot of information about Xinjiang is exactly the opposite of the facts and some doesn't even exist. I feel frustrated about some of them," Zhang said.
Xinjiang needs to combat old problems, he said, adding that they were "severe threats from terrorists, separatists and extremists."
"The current international environment could provoke and influence the three forces within Xinjiang. The penetration of such forces also has its historical background, so it takes time to combat them. But the overall situation of Xinjiang remains stable and it is obvious that it's getting better and better."