A mother and three of her children were among the fourteen people killed when two suicide bombers struck the entrance of a military base and a checkpoint near the headquarters of the Southern Transitional Council (STC) in Aden.
The family died of wounds on Sunday, medical sources said.
Some 40 people were also injured when the bombers blew up their vehicles in the Gold Mohur area of Aden's Al Tawahi district at 5.20pm on Saturday. ISIL claimed responsibility for the attack through its propaganda arm Amaq.
During the chaos in Yemen over the past few years, ISIL has repeatedly attacked Aden, where the government is based, claiming hundreds of victims and mainly targeting government forces.
According to officials the death toll included a member of Aden's elite counter-terrorism forces.
Two other attackers wearing explosive belts also tried to climb over the external gate of the military base to reach the inside but were shot dead by guards before they could blow themselves up.
Local shops and houses were severely damaged in the attack while the force of the blasts shattered windows in the headquarters of the STC's headquarters. The secessionist body, which is based in Aden, is calling for an independent southern Yemen.
Meanwhile in Al Hodeidah province, Houthi fighters on Sunday released and forcefully recruited dozens of prisoners, UAE state news agency Wam reported, citing military sources.
According to Wam's sources, the prisoners were released to boost the Houthi ranks, after suffering heavy losses in lives and equipment during battles along the country’s Red Sea Coast.
Over the last couple of days sixty Iranian-backed Houthi militias were killed following air strikes carried out by Arab-led coalition forces.
According to Yemeni military sources,14 Houthis were killed on Saturday evening in clashes north of Hayes and Al Hamili, Wam reported.
Coalition forces carried out air strikes in an effort to destroy Houthi reinforcements and vehicles along the Red Sea Coast.