Sana'a, Yemen  -  At least seven people, including three soldiers, were killed in fierce fighting between government forces and Shiite rebels in northern Yemen on Saturday, a day after a bomb attack near a mosque left 13 worshippers dead, local sources said.

The clashes broke out early in the day in the districts of Haidan and Munabeh in the north-western province of Saada, which borders Saudi Arabia, the sources told Deutsche Presse-Agentur dpa.

They said three soldiers were killed and two injured when insurgents loyal to the outlawed Believing Youth rebel group attacked an army patrol in Munabeh.

Four rebels were later killed when army soldiers manning a checkpoint in Haidan opened fire on a car carrying them.

Skirmishes were reported in three other locations in Saada, but details on casualties were sketchy.

The fighting follows Friday's motorcycle bomb attack on the Bin Salman mosque in the provincial city of Saada that left 13 dead and 50 injured.

Local sources in Saada have said a regional army commander, Askar Ali al-Zuail, was the target of the bombing, but he survived unharmed.

Al-Zuail is an aide to Brigadier General Ali Mohsen al-Ahmar, the military commander of the north-western region, who has been leading the battle against the Shiite rebels in Saada since mid-2004.

In a statement carried by the official Saba news agency, the Interior Ministry accused the Shiite rebels of carrying out the attack. The leader of the rebel group, however, denied any connection to the bombing.

"We criticize and condemn this regrettable act ... and extend condolences and sympathy to the victims' families," al-Houthi said in a statement sent to journalists by email.

"We insist on the need for an objective fact-finding investigation to find out the party behind those acts," the statement said.

Al-Houthi, whose Believing Youth group fought with government forces in Saada for more than three years, said the attackers "intended to blow up the war anew and foil all efforts for establishing peace and reconciliation." (dpa)