* Three killed in northern Yemen clashes, death toll at 58
* Government blames Houthis of blocking implementation of ceasefire
* Fighting cast a shadow over reconciliation talks
* Yemeni intelligence officer injured by explosion in his car
By Mohammed Ghobari
SANAA, Nov 3 (Reuters) - At least three people were killed in fighting between rival Muslim clans in northern Yemen on Sunday, a local official said, bringing the death toll from five days of clashes to 58 as the government tried to broker a ceasefire.
The battles between Shi'ite Muslim Houthi fighters and rivals from a Sunni Salafi group erupted last Wednesday in the mountainous Saada province, which has long been outside the control of the central Yemeni government.
Yemen's stability is a priority for the United States and its Gulf Arab allies because of its strategic position next to oil exporter Saudi Arabia and shipping lanes, and because is home to one of al Qaeda's most active wings.
The sectarian fighting in the north has cast a shadow over national reconciliation efforts launched this year after long-serving President Ali Abdullah Saleh was forced to step down following a popular uprising in 2011.
The Salafis say the fighting began with a Houthi attack last week on their Damaj stronghold, about 40 km from the Saudi border. All the 58 dead are from the Salafi side, according to a Salafi spokesman. The Houthis have reported no casualties.
The Houthis accuse the Salafis of igniting the strife by bringing thousands of foreign fighters into Damaj. The Salafis say the foreigners are students there to study Islamic theology.
The head of a presidential committee tasked with ending the fighting said Houthi fighters had stopped him and a Red Cross delegation from entering Damaj, despite an agreement to stop the fighting and evacuate the wounded.
"The Houthis are blocking the implementation of the ceasefire agreement," Yehia Abuesbaa told Reuters by phone from a checkpoint at the entrance to Damaj.
Abuesbaa said the Houthis, who had won the release of six comrades held by pro-Salafi fighters from the Al-Ahmar clan in the neighbouring Omran province, had demanded that the six be flown by an army helicopter to Saada before they allowed the evacuation of about 70 seriously injured people from Damaj.
Surour al-Wadi'i, a spokesman for the Salafi group, said the Houthis were pushing ahead with their offensive on Damaj. "The fighting hasn't stopped," Wadi'i told Reuters by phone from Damaj as sounds of explosions echoed in the distance.
Two Houthi officials contacted by Reuters did not answer their phones and a spokesman had yet to reply to a message left on his phone.
The Salafis say Damaj, which is near the Houthi-controlled city of Saada, has been under rebel siege for weeks and say rockets have hit, among other targets, student dormitories at a religious school.
Saada province is the base for a long-running Houthi rebellion against the government. Complaining of social, religious and economic discrimination in Yemen, the Houthis fought several battles with government forces between 2004 and 2010, when a truce was announced.
Saudi Arabia was drawn briefly into the conflict in 2010 when rebels crossed into its territory.
Apart from the Salafi-Houthi conflict, Yemen is struggling with southern secessionists and militants from al Qaeda in the Arabian Peninsula, which has plotted attacks on U.S. airliners, Saudi targets, and Yemeni security installations and officials.
A colonel in the Yemeni domestic intelligence service was seriously wounded in an explosion inside his car in the southern port city of Aden on Sunday, witnesses said. A local official said the attack bore the hallmarks of al Qaeda. (Additional reporting by Mohammed Mukhashaf in Aden,; Writing by Sami Aboudi; Editing by Pravin Char)