Army and police officers loyal to the Shi’ite al-Houthi group march during a demonstration in Yemen’s capital Sanaa on June 4. REUTERS/Khaled Abdullah

SANAA — Shi’a rebels fought Yemeni soldiers just 25 miles (40 km) northwest of the capital Sanaa on Wednesday, an official said, as they try to tighten their grip in the area before next year’s presidential election.

The government is considering giving greater autonomy to Yemen’s regions after the military split and the state’s control over its territory crumbled in the wake of 2011 Arab Spring protests which ousted veteran leader Ali Abdullah Saleh.

The official, deputy governor of Northern Amran province Ahmed al-Bakri, said Houthi rebels were fighting government troops backed by tribal militia for a second day in several villages.

Tribal sources said Houthi insurgents were also fighting government troops in two districts on Sanaa’s western outskirts, also about 25 miles from the center of the capital.

There were no immediate reports of casualties.

A power struggle between President Abd-Rabbu Mansour Hadi and his predecessor escalated this week, with government forces raiding a pro-Saleh TV station. They have also surrounded a mosque in central Sanaa they say his supporters were planning to use as a base to attack the presidential palace.

Yemen is also battling a secessionist movement in the south as well as al-Qaeda militants whom Gulf neighbors and the United Sates view as a critical threat to regional security.