People gather at the site of a car bomb attack that killed the governor of Yemen's southern port city of Aden December 6, 2015. Jaafar Mohammed Saad was killed on Sunday when a suicide bomber rammed his car into the governor's convoy in the western part of Aden city, residents and a local official said.  [Photo/Agencies]

FLAMES

Sunday's explosion could be heard about 10 km (seven miles) away, residents said. Photos posted by local news websites showed a car in flames with a plume of smoke rising from it.

The victims were taken to the Jumhouriya Hospital, the main state medical facility in Aden which Saad had re-opened in a ceremony two days earlier.

Medics said the body of Saad and the others who were killed were burned beyond recognition.

Security had been a main concern for Hadi and his Arab allies since he returned to Aden last month to oversee an offensive by his forces and Arab allies to drive the Houthis from the strategic city of Taiz.

In October, the government of Prime Minister Khaled Bahah was forced to relocate to Saudi Arabia after four coordinated suicide bombings by Islamic State killed at least 15 people, including four Emirati soldiers.

Saad had been a general in the army of the former southern Yemen before the Marxist state merged with northern Yemen in 1990. He was appointed governor in October.

Local officials said Saad, who fought in the 1994 civil war for southern forces against the northerners, had lived in exile in Egypt and Britain before he returned earlier this year at Hadi's request.

In a separate incident, residents said a field commander of a local militia group that had helped drive the Houthis out of Aden in July was shot and killed by unknown assailants in the west of the city on Sunday.

It was not immediately clear if that attack was linked to Islamists or if it was a result of the general lawlessness gripping Aden.