Yemeni government forces have launched a fresh assault on insurgents in the north-west of the country.
At least 70 rebels are reported to have died in heavy clashes from Wednesday to Thursday night in Saada province.
The rebels are followers of radical cleric Hussein al-Houthi, who was killed by security forces in September after starting an uprising.
The government launched its latest attack after negotiations failed, Yemen's Saba news agency said.
Security forces blamed the renewed violence on Hussein al-Houthi's father, Badr al-Din al-Houthi.
Last month he criticised the authorities for detaining hundreds of rebels despite a government deal to free them following the ceasefire.
The insurgents belong to the Zaidi sect, a branch of Shia Islam.
Yemen says the group preaches violence against the US and Israel in mosques.