Twin bombings claimed by Islamic State group targeted the Yemeni army in second city Aden Monday killing at least 41 people, most of them would-be recruits, a military official said.
A suicide bomber killed 34 people queueing to enlist at a recruitment centre near the Badr base in the Khormaksar district, said Brigadier General Nasser al-Sarei, commander of special security forces.
A second explosion inside the base afterwards killed seven soldiers, he said.
In a statement posted online, IS said one of its militants detonated an explosives belt among "apostate soldiers" at a recruitment centre, followed by a bomb that exploded at the gate of the Badr base.
Aden is the headquarters of the government of President Abedrabbo Mansour Hadi as it battles Shiite rebels who control the capital Sanaa.
The port city has seen a spate of attacks in recent months claimed by Al-Qaeda or its jihadist rival IS.
Government forces drove Huthi rebels out of Aden in July with support from a Saudi-led coalition.
The two jihadist groups exploited the power vacuum created by the conflict in Yemen to expand their presence in the south and southeast.
But over the past two months, government and coalition forces have hit back, also driving the jihadists out of the Hadramawt provincial capital of Mukalla, which they had controlled for a year.