Renewed fighting between Sunni tribesmen and Shia Houthi rebels advancing into a town in central Yemen has killed dozens of people, as part of a growing struggle over territory and influence between the two sides.

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Sources told Al Jazeera on Monday that clashes between Houthi fighters and Sunni tribes backed by al-Qaeda in the Arabian Peninsula (AQAP) killed 67 Houthis in the Radaa district of Bayda province, 130km south east of Sanaa.

An attack on a Houthi gathering killed 23 Shia fighters, 15 were killed in a suicide car bombing and 29 others were killed by shelling and an attack at two posts. 

Intense fighting erupted overnight, with the town rocked by explosions, rocket-propelled grenades and artillery by both sides. 

Al Jazeera's Omar Al Saleh, reporting from Sanaa, said Sunni tribes had joined the fight against the Houthis, wary of the Shia rebels takeover of most of Yemen.

Radaa is a mixed Sunni-Shia town but has been a stronghold of AQAP. Houthis have frequently clashed with al-Qaeda-linked fighters.

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Sunni tribesman also attacked rebel positions northeast of Radaa and along a road connecting the town in Bayda province to neighbouring Dhamar, a Shia-populated province taken last week by the rebels.

The rebels, known as Houthis, have been facing fierce resistance from Sunni tribesmen and AQAP as they seek to expand their territory after seizing the capital Sanaa and the Red Sea port city of Hodeida.

Hailing from the northern highlands and championing the interests of the Zaidi community which make up a fifth of Yemen's 25 million population, the Houthi rebels are increasingly imposing their authority outside the capital as well as in it.

Yemeni authorities and Saudi Arabia have accused Iran of backing the Houthis.

Source: Al Jazeera and agencies