SANAA, Yemen (AP) — Four people were killed Sunday in Yemen's port city of Aden by a car bomb that targeted two senior government officials, who survived, security officials said.

The explosion targeted the convoy of Agriculture Minister Salem al-Socotrai and Aden’s Gov. Ahmed Lamlas in the district of Tawahi, the officials said.

The explosion killed at least four people among Lamlas’ companions and wounded at least five others who had been passing by, they said. The casualties were taken to hospitals for treatment, the officials said.

The explosion damaged several buildings in the area, quickly sealed off by security forces, according to the officials who spoke on condition of anonymity because they were not authorized to brief media.

Prime Minister Maeen Abdulmalik Saeed called the explosion a “terrorist attack” and ordered an investigation.

No one immediately claimed responsibility.

Aden has been rocked by several explosions in the past years, which have been blamed on local affiliates of al-Qaida and the Islamic State groups.

Aden has been the seat of the internationally recognized government of President Abed Rabbo Mansour Hadi since the Iranian-backed Houthi rebels took over the capital, Sanaa, triggering Yemen’s civil war.

The president fled to Aden then to Saudi Arabia, which led a military coalition the following year to try to restore Hadi to power and threw its support behind his internationally backed government.