Shots fired at convoy of UN's Yemen envoy, no one hurt-security source
The source, who had been travelling in the convoy in the Yemeni capital Sanaa, said guards escorting the convoy had opened fire on the attackers who then fled the scene.
Benomar is trying to push forward a dialogue on national reconciliation, part of a power transfer deal prompted by mass protests in 2011 that forced veteran president Ali Abdullah Saleh to step down after 33 years in office.
The talks have got stuck mainly on disagreement over demands by southern separatists to restore the state that merged with North Yemen in 1990.
Last week Benomar, who played a key role in the power transfer deal, accused elements in Saleh's former administration for problems facing the reconciliation talks. He told Yemeni state television the United Nationswould punish those who tried to block the dialogue.
As well as the southern secessionist movement, Yemen is also grappling with an insurgency by Islamist militants linked to al Qaeda and a rebellion in the north, which flared last month into full-blown sectarian clashes between Sunni Salafis and Shi'ite Houthi rebels in which more than 100 people have been killed.