Sixteen Shiite rebels and five soldiers were killed in clashes in northern Yemen Friday, a day after 15 local aid workers were kidnapped, officials said. Rebels loyal to leader Abdul-Malik Al-Houthi attacked and damaged a government building in the northern province of Amran, a local government source said. As the government offensive entered its fourth day in Yemen's northern mountains Friday, the fighting shifted away from Saada town toward Amran, just 70 km north of the capital Sanaa, a security official said. The new fighting came a day after Saada provincial Governor Hassan Mohammed Manaa vowed that the state of emergency imposed early Tuesday would be “lifted only when the rebels have been crushed.” In comments carried by the website of the defense ministry's September 26 newspaper, Manaa accused the rebels of kidnapping 15 Red Crescent staff from a camp in Saada for people displaced by the fighting. “They blindfolded them, beat them and insulted them,” he said, charging that they had also ransacked a help center for farmers in Anad district. “Over the past four days, 17,000 families have been forced to flee their homes,” Manaa said, adding that the rebels had killed four leaders of the Al-Azl tribe and 15 other civilians, including women and children. Yemen Thursday announced conditions for a ceasefire to end a government offensive against the rebels in the north of the mainly Sunni Muslim Arab country. The rebels rejected the truce offer and denied holding any kidnapped civilians. Officials say the rebels want to restore a form of clerical rule prevalent in Yemen until the 1960s. The rebels say they are defending their villages against government oppression.