The cease-fire between the Houthi and Salafi militants came after three days of battle, the Yemen Post reported.
Yehia Mansour of the presidential committee that negotiated the truce told reporters the government had deployed two army battalions to make sure the cease-fire was adhered to by both sides.
Serour al-Wadie, a spokesman for the Salafis, confirmed more than 100 of its fighters had died since Wednesday.
Thousands of Salafists demonstrated in Sana'a Saturday in support of their group's fighters, the Post said.
The latest violence came on the heels of fighting last month that resulted in 42 people being killed in Amran and Ibb provinces, the newspaper said.