Thirteen people were killed in an attack on a police station in China's restive region of East Turkestan (Xinjiang), the official Xinhua news agency reported on Saturday.Three police officers were "lightly wounded" in the attack on Saturday morning, but there were no casualties among the public, the news agency said citing the local government."The gangsters drove a vehicle to ram the building of the public security bureau of Kargılık County in southern Xinjiang and set off explosives," it said.East Turkestan is the traditional home of Muslim Uyghurs who speak a Turkic language, and China has blamed previous attacks on separatists it says seek to establish an independent state.In 2012, seven attackers were shot dead after killing 13 people in a knife attack in Yecheng, also known by its Uyghur 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 the region's regional 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 the region have arrested or tried 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 others for an attack on Beijing's central Tiananmen Square.Resource-rich and strategically located on the borders of central Asia, East Turkestan has been plagued by violence for years, but exiled Uyghur groups and human rights activists say the government's own repressive policies in the region have provoked unrest, something Beijing denies.Chinese President Xi Jinping said earlier this year that the Kashgar region, which sits in the far west of East Turkestan, is "the front line in anti-terrorism". The Silk Road city of Kashgar has been at the centre of much of the unrest in the region. Yecheng is in the Kashgar prefecture, and is more than 1,500 kilometres southwest of Urumqi.