Fighting in central Yemen town of Radda between the Shi’ite Houthi rebel movement and the Qifa tribe have killed at least 250 people over the last three days, according to government officials.

The Houthis, whose traditional strength is in north Yemen, took control of the capital Sana’a in September and have since expanded south, taking on government forces despite a power-sharing agreement being signed and also battling al-Qaida militants and other groups.

A Qifa counter-attack has driven them out of the Manasih area of Radda, officials reported.

President Abed Rabbo Mansour Hadi spoke out against the Houthis for the first time since they seized Sana’a on Sunday, saying their apparent bid to expand militarily across Yemen “cannot be understood or accepted after they signed the peace and national partnership agreement.”

But they are believed to be working in alliance with supporters of former president Ali Abdullah Saleh, who was overthrown in 2011.