A suicide bomber killed at least 14 soldiers in Aden on Wednesday, in the latest attack on Yemen's second city claimed by militants of the Islamic State group.

The southern port city has been the headquarters of forces loyal to President Abedrabbo Mansour Hadi and his backers in a Saudi-led military coalition but has seen growing violence by IS group and its militants rival Al-Qaeda.

"A man detonated his explosive vest among soldiers," a military source said.

The troops were attending a training session run by Sudanese forces of the Saudi-led coalition, another military source said.

The bomber, who was disguised as a soldier, attacked the Ras Abbas camp in the west of Aden.

The blast came a day after Al-Qaeda claimed an attack on the convoy of Aden's governor and police chief in which four militants were killed.

Since March last year, when the Saudi-led coalition intervened in support of Hadi, IS group has ramped up its operations in Yemen.

Its rival Al-Qaeda also has a significant presence, expanding its presence in the south and southeast.