Yemen's army has launched a major offensive in the country's northern mountains to quell a six-week rebellion, which in the past two days alone has killed 50 soldiers and rebels.
Government officials and tribal chiefs said Thursday more than 2,000 Yemeni troops have been deployed against supporters of Hussein Badr Eddin al-Houti, a Shiite Muslim whom the government regards as an outlaw.
Long-simmering tension between the government and al-Houti erupted into armed conflict on June 21 when security forces tried to arrest his supporters in Sa'dah, a city about 124 miles northwest of the capital San'a.
More than 500 soldiers and rebels have been killed since the conflict began.
Last month President Ali Abdullah Saleh ordered a temporary halt to military operations against al-Houti's forces, who are holed up in the Jabal Maraan mountains outside Sa'dah, to give mediators a chance.
But the fighting continued.
Government officials, speaking on condition of anonymity, said heavy artillery, tanks, helicopter gunships and fighter jets have been backing Yemeni troops. The government has also recruited armed tribesmen from outside the area to fight al-Houti's followers.
"We've been ordered to end the standoff once and for all," an official said Thursday, as the fighting went on.
Tribal elders said the fighting had killed about 50 people and wounded dozens since the offensive began late Tuesday. The elders, who spoke on condition of anonymity, said most of the casualties were soldiers, who have since been evacuated to hospitals in San'a.
The elders said, however, that attempts were still being made to mediate an end to the dispute, although many past attempts have failed.
Yemen's government is offering a $55,000 reward for the capture of al-Houti, who is accused of sedition, attacking government buildings and security forces, forming an illegal armed group and inciting people not to pay taxes.
His group is also said to encourage anti-American sentiment through mosque speeches and demonstrations.
In a statement posted on an Internet site Thursday, a previously unknown Islamist group claiming links to al Qaeda expressed solidarity with al-Houti and condemned Yemen's government because "they opened the country of Muslims to the crusader forces."
The group gave its name as Tawhid wa al-Hijra, which means Monotheism and Flight — a reference to the departure of Islam's 7th century prophet, Muhammad, to Mecca with his followers and going to Medina to escape persecution.
Yemen's government has supported the U.S.-led war on terrorism and has received American military assistance.
The government maintains it is pursuing al-Houti as an outlaw, not as a Shiite. Shiites represent about 30 percent of the Yemeni population and generally do not suffer discrimination.
By Ahmed Al-Haj