Gunmen on a motorbike shot dead a top official of Ansarullah movement in the capital on Wednesday, a security source said.
Abdul Karim al-Khiwani, a member of the Revolutionary Committee of the Huthis, was attacked by two gunmen, the source said.
The Yemeni television, al-Massira confirmed the report.
Khiwani was shot close to his home, the source added.
He had represented Ansarullah movement during national talks stipulated by a UN-backed peace agreement that ended a year of deadly protests against President Ali Abdullah Saleh, who stepped down in February 2012.
The Huthis have been in effective control of Sanaa since September, when they flushed out al-Qaeda-linked militants from the capital.