Security officials in Yemen say at least eight people were killed as clashes raged between al-Qaida militants and Shiite rebels who are fighting for the control of a city in the country's central heartland.

The officials said residents of Radda, in the province of Bayda south of the capital, have fled because of the intense fighting, which killed five rebels and three militants early Saturday.

The Shiite rebels overran the city a day earlier.

In another province south of the capital, a security official said an explosion killed four Shiite rebels when it hit their convoy travelling to the city of Ibb, where the Shiites have been fighting tribesmen allied with Islamists.

All officials spoke on condition of anonymity because they were not authorized to speak to the media.