(CNN) -- Shiite militants in Yemen captured dozens of soldiers and local tribe members and occupied a military post on Tuesday, a Yemeni official authorized to talk to the media said.
The government is negotiating the release of the captives and the evacuation of the post, the official said.
The militants -- Houthi rebels in northern Yemen -- began a revolt in 2004. A cease-fire has been in effect since February.
The conflict is believed to be both separatist -- over who will have power in the area -- and sectarian -- whether Shiite Islam will dominate, even though the majority of Yemenis are Sunni. The rebels are supporters of slain Shiite cleric Hussein al-Houthi.