(Adds exiled Uighur group comment)
By Adam Jourdan
SHANGHAI, June 21 (Reuters) - Chinese police shot dead 13 attackers in the restive far-western region of Xinjiang on Saturday after they rammed a car into a police station and detonated explosives, Xinhua news agency said, in the latest of a series of attacks to worry Beijing.
China has been toughening its response to violent crime after a spate of attacks around the country, centred on Xinjiang, the traditional home of Muslim Uighurs.
China has blamed previous attacks on Islamist separatists in the region, who they say are looking to establish an independent state there called East Turkestan. It was not immediately clear who was responsible for Saturday's violence.
"The gangsters drove a truck to ram the building of the public security bureau of Yecheng County in southern Xinjiang and set off explosives. Police shot and killed 13 attackers at the scene," Xinhua said, adding that three police were slightly wounded.
In 2012, seven attackers were shot dead after killing 13 people in a knife attack in Yecheng, also known by its Uighur name of Kargilik, a remote town on the road leading to China's mountainous border with Pakistan.
China has been on edge since a suicide bombing last month killed 39 people at a market in Xinjiang's capital, Urumqi. In March, 29 people were stabbed to death at a train station in the southwestern city of Kunming.
The rise in violence has prompted a crackdown on violent crime. Authorities in Xinjiang have arrested dozens of suspects in recent weeks for spreading extremist propaganda, possessing banned weapons and other crimes.
China also executed over a dozen people for terrorist attacks in the region earlier this month and three for an attack on Beijing's central Tiananmen Square.
Resource-rich and strategically located on the borders of central Asia, Xinjiang has been plagued by violence for years, but exiled Uighur groups and human rights activists say the government's own repressive policies in Xinjiang have provoked unrest, something Beijing denies.
"The crackdown against the Uighur population is making it hard for people to bear," Dilxat Raxit, spokesman for the World Uyghur Congress, the largest group of exiled Uighurs, told Reuters by email.
"Opening fire and killing those resisting, and accusing them of terrorism while skirting the root causes, this will only lead to the situation in the region becoming worse."
President Xi Jinping said earlier this year that the Kashgar region, which sits in the far west of Xinjiang, was "the front line in anti-terrorism". The Silk Road city of Kashgar has been at the centre of much of the unrest. Yecheng is in the Kashgar prefecture, and is more than 1,500 km southwest of Urumqi.
Chinese leaders have also been directing investment into Xinjiang. Xi pledged last month to alleviate poverty and improve ethnic unity in the region, the most direct indication yet that China's leaders want to address the causes of violence. (Reporting by Adam Jourdan; Additional reporting by Ben Blanchard in BEIJING; Editing by Simon Cameron-Moore and Nick Macfie)