Two gunmen on a motorbike shot dead a top official of the Shiite Huthi militia in the Yemeni capital on Wednesday, a security source said.
Abdul Karim al-Khiwani, who was a member of the Revolutionary Committee of the Huthis that control Sanaa, was shot close to his home in an incident confirmed by Huthi television channel Al-Massira.
A journalist who won Amnesty International Special Award for Human Rights Journalism under Threat in 2009, he had been head of the militia's media department.
On Wednesday, Amnesty International urged a quick probe of the "despicable killing of a leading journalist and activist," saying Khiwani had a history of being harassed for his "outspoken journalism and peaceful activism."
"His despicable killing today smacks of a politically motivated assassination," said deputy regional director Said Boumedouha.
The London-based group said Khiwani had been jailed several times during the rule of former president Ali Abdullah Saleh.
Khiwani represented the Huthis during national talks held under a UN-backed deal that ended a year of deadly protests against Saleh, who stepped down in February 2012.
The talks concluded in January 2014 with a plan to turn the republic into a federation of six regions -- a blueprint the Huthis strongly oppose.
The Huthis have been effective masters of Sanaa since September, expanding their zone of control to neighbouring regions and to the shores of the Red Sea.
President Abedrabbo Mansour Hadi escaped last month from house arrest in Sanaa and has fled to second city Aden in the south, where he is attempting to re-establish authority.
Tension remains high in Sanaa, where groups opposing the Huthis have been staging frequent demonstrations demanding their pullout and voicing support for Hadi.
The Huthis fought six wars with the Yemeni government between 2004 and 2010.
A key US ally in the fight against Al-Qaeda, Yemen has descended into chaos since the departure of Saleh, who has been accused of backing the Huthis.
Source: AFP