Yemen's prime minister has escaped unharmed after unknown gunmen opened fire on his convoy, a senior aide said.
Ali al Sarari told The Associated Press the gunmen were riding in a vehicle without licence plates. Mr al Sarari said they opened fire at the three-car convoy of prime minister Mohammed Salem Bassindwa, spraying the speeding vehicles with bullets.
Mr al Sarari said some of the vehicles were pockmarked but Mr Bassindwa escaped unharmed.
It was not clear who was behind the attack but militants have carried out a number of assassinations, mainly against security officers.
The security officials said Hassan al Mansouri was killed in Labous, in the southern Lahj province, following a day of clashes between local tribesmen and suspected members of al Qaida in the area.
They say Mr al Mansouri had organised local tribes in a campaign to weed out the militants from the area.
The officials said they suspect the killers are from al Qaida in the Arabian Peninsula. Washington considers the group as the most dangerous al Qaida branch to threaten US interests, and has waged drone attacks against it in Yemen.
Yemen security forces also battle against the group, which has killed security officials in the past.