The official said the attackers, members of a secessionist group, attacked the outpost with vehicles topped with machine guns, China's Xinhua News Agency reported.
An army official confirmed the attack, saying "army forces swiftly launched a large-scale manhunt" for the attackers, arresting one person.
Identities of the attackers are unclear, the army officials aid.
A dozen people, including children, were killed Friday when artillery shells hit a funeral attended by southern separatists.
Notable deaths of 2014 [PHOTOS]
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