Sixteen policemen were killed and several others injured on Monday after a border patrol armed police division was attacked in China's Muslim-majority northwestern Xinjiang province, just four days ahead of Olympics.
Two attackers drove a lorry into the police station in Xinjiang city of Kashi this morning and threw two grenades causing explosions, the Xinhua news agency reported.
They threw two grenades, which exploded, before they were arrested, Xinhua said.
China has repeatedly warned of terrorist threat emanating from Xinjiang, saying the separatists militants there were planning to attack the Olympics.
The rights groups and members of the ethnic Muslim Uighur population in Xinjiang, however, have accused the government of exaggerating the threat as cover to crackdown on all forms of dissent. Xinjiang has about 8.3 million Uighurs.
China has deployed more than 100,000 security personnel to provide security for the Games, which begin on August eight and end on August 24.