Yemeni troops killed 17 Shiite rebels in overnight clashes in the rugged mountainous north as the army stepped up its all-out offensive, the official Saba news agency reported on Thursday.
Four other rebels, who are also known as Huthis and are seeking an end to the current form of government, were arrested as they fled the battleground in Saada province, a local official told Saba.
"The army and security forces have inflicted heavy losses upon the saboteurs and the rebels whether in terms of lives or equipment," the official said.
Jet fighters roared overhead, striking rebel posts as troops exchanged fire with Huthi fighters, who during the gunfight wounded two civilians, one of them severely, the official added.
The army has also destroyed several vehicles that were carrying aid, ammunition and weaponry to the rebels, he said.
The Yemeni government launched operation "Scorched Earth" on August 11 but last Friday said it would observe a ceasefire in response to requests from aid agencies. But fighting resumed only four hours after the truce was announced.
Local and international aid groups have repeatedly warned of worsening humanitarian conditions among tens of thousands of civilians displaced by the recent flare-up of fighting and now living in refugee camps.