The Houthis said on Tuesday that the group has quit the national dialogue in protest at the killing of Ahmad Sharafeddin, who was gunned down by unknown gunmen in Sana’a earlier in the day.
Security officials said the leading Houthi figure was shot dead on his way to a hotel in the capital where the talks are being held.
The university professor of law was the second representative of the Houthi movement to the negotiations to be assassinated.
Lawmaker Abdulkarim Jadban was killed in a similar attack in November 2013.
The killing of the second Houthi envoy comes as the Shia fighters are engaged in deadly clashes with the Hashid tribe in the northern Yemen.
The Houthis say Hashid is helping Salafist groups fighting against them in the city of Dammaj and have turned the city into a safe haven for thousands of foreign militants.
Nearly two dozen people have been killed on both sides in the past few days.
Dammaj has been the scene of bloody clashes between Houthi fighters and Salafi groups in Yemen’s Northern Province of Sa’ada since October 2013.
A Yemeni government committee recently mediated a ceasefire between the Houthis and Hashid, after months of clashes in Sa’ada.
The Houthis, led by Sheikh Abdel-Malek al-Houthi, control parts of northern Yemen.
They blame the government of political, economic, and religious marginalization of the country’s Shia community and violating their civil rights.
