Yemeni authorities say they have killed 46 supporters of a dissident Muslim cleric in the north of the country.
Yemeni troops were also reported killed in the operation
An interior ministry statement quoted by the Saba state news agency said the raid targeted anti-government preacher Hussein al-Houthi and his supporters.
Soldiers backed by helicopters laid siege to several guerrilla targets in Saada, 240km (150 miles) north of the capital, Sanaa, the agency reported.
Yemen has accused the Shia cleric of sedition and anti-American extremism.
At least 12 government soldiers are also reported to have died in the operation against the rebels, which the ministry said started four days ago when police attempted to arrest the cleric.
Since then, at least 35 rebels had been wounded and 43 had been arrested, according to the government.
Officials said a large cache of automatic rifles, grenade-launchers and land mines had been recovered from the homes of Mr Houthi's supporters.
Security sources quoted by the Reuters news agency say Mr Houthi, who belongs to the Zaidi sect of Yemen's Shia Muslim minority, heads a rebel group which has taken part in violent protests against the US and Israel.
Yemen's government recently launched a crackdown against suspected extremists linked to al-Qaeda.
It has not claimed Mr Houthi's rebels are linked to the group.