A car bomb in a central square in Yemen's port city of Aden on Sunday targeted the city's security chief for the second time in a week and killed four soldiers, local officials and witnesses said.
The bomb exploded in front of the provincial government building and wounded eight people although security chief, Shelal Ali Shayyeh, was unharmed, the sources said.
A suicide car bomb planted outside Shayyeh's home on Thursday ended a period of relative calm in Aden, the temporary base of Yemen's internationally recognized government.
The attacks follow gains by Yemeni and Emirati forces based in Aden, who have mounted an offensive against al Qaeda militants in towns on the south coast.
Al Qaeda in the Arabian Peninsula (AQAP) has taken advantage of chaos in Yemen since its civil war began last year to win control over swathes of southern and eastern Yemen.