An explosive-laden car went off near a building of Yemen's National Security Agency in the southeastern province of Hadramout on Saturday, causing no casualties, a provincial police officer said.
"Initial reports showed that an al-Qaida suicide bomber slammed his explosives-packed vehicle into the main gate of a building belonging to Yemen's National Security Agency in the coastal city of Mukalla, Hadramout's provincial capital," the source said.
"A powerful explosion in front of the center of the national security agency caused serious damage to the neighboring buildings but no casualties," the police officer said.
A military official said that "a car bomb ripped through the national intelligence department in the country's port city of Mukall, followed by a rocket attack on the same area."
"Rocket-propelled grenades fell about half an hour after the bombing on the same area, where there were armored vehicles and soldiers, trying to secure the neighborhood after the blast," the military official added.
After the blast, police shut off the road, and ambulances rushed to the scene as flames rose from the building, local residents said.
There was no immediate claim of responsibility for the attack.
Earlier on Tuesday Yemen's armed forces launched an all-out offensive with more than 1,600 soldiers and 400 security personnel against several al-Qaida hideouts in the country's southern territories.
The Yemen-based al-Qaida branch, known locally as Ansar al- Sharia, or Partisans of Islamic Law, warned the military authorities not to target al-Qaida strongholds and vowed to launch more attacks in revenge.