A suicide bomber killed 35 soldiers and wounded around 50 others today at a military camp in Yemen's southern city of Aden, where jihadists are active, military and medical sources said.
The attacker detonated his explosives belt as hundreds of troops gathered to receive their monthly pay at the barracks in Al-Sawlaban near the city's international airport, a military source said.
The so-called Islamic State group claimed responsibility for the attack.
Yemeni authorities have for months pressed a campaign against jihadists who remain active in the south and east of the war-torn country.
IS and its jihadist rival Al-Qaeda have taken advantage of a conflict between the government and the Huthi rebels, who control the capital Sanaa, to bolster their presence across much of the south.
IS and Al-Qaeda have carried out a spate of attacks in Aden, Yemen's second city and headquarters of the internationally recognised government whose forces retook the port from the Huthis last year.
Al-Qaeda has long been the dominant jihadist force in Yemen, located next to oil-flush Saudi Arabia and key shipping lanes, but experts say IS is seeking to supplant its extremist rival.
In August an IS militant drove his explosives-laden car into an army recruiting centre in Aden, killing 71 people in the deadliest jihadist attack on the city in over a year.
On Monday, Yemeni authorities arrested eight suspected IS jihadists implicated in a spate of attacks targeting security personnel in the city this year.
A Saudi-led coalition has since March 2015 supported loyalist forces fighting the Huthi rebels.