A car bomb has killed a Yemeni intelligence officer and wounded three others in an attack in the capital, Sanaa.

The blast on Sunday was the latest in a series of attacks targeting military personnel in a country that is grappling with several armed revolts and negotiating a difficult political transition.

AFP and Reuters news agencies reported that explosives were planted inside a vehicle being driven by an intelligence officer. They detonated outside the oil ministry, the agencies reported.

AFP named the dead man as Colonel Mohammed Fadhel Hussein, citing an anonymous security source.

A bodyguard travelling with Hussein was wounded, in addition to two passers-by, the official said.

Al Jazeera's Mohamed Vall, reporting from Sanaa, said that the blast was "limited" but placed under the victim's seat.

The attack comes days before the three-year anniversary of the uprising that toppled Ali Abdullah Saleh from the presidency.

Many Yemenis say that the apparatus of Saleh's regime is still in place. More than half of the present cabinet is loyal to the former president.

Yemen is also facing a worsening security situation with frequent assassinations, bomb blasts and tribal fighters taking control in state districts.

A fragile ceasefire is holding in Arhab, 40km north of Sanaa, after months of fighting between Shia Houthis and Sunni tribes.

A series of kidnappings of foreigners have also compelled foreign governments to warn of a growing threat in the country.

Source: Al Jazeera and agencies