At least 25 new recruits were killed and 25 others wounded when a suicide bomber blew himself up inside a police compound in the southern Yemeni city of Mukalla on Sunday in an attack claimed by DAESH, medical and security sources said.
The victims were queuing up to register when the bomb went off, the sources said.
Today's attack is the second deadly blast in four days to hit the city, a hub for Al Qaeda before the militant group was driven out last month in an offensive by Yemeni troops backed by a Saudi-led coalition.
Mukalla's security director Mubarak Al Awthaban survived the attack, he was at a nearby office when the suicide bomber struck the Fowa camp in the southern part of the city, security sources said.
Before being forced out, Al Qaeda militants took advantage of more than a year of war between the Iran-allied Houthis and supporters of the Saudi-backed President Abd Rabbu Mansour Hadi to carve out a mini-state stretching across much of the southern coast, including Mukalla.
Their militant rivals in Yemen's branch of DAESH have carried out a series of suicide attacks on all parties to Yemen's tangled conflict.
The growing DAESH threat has led the Houthis and the Yemeni government to embark on peace talks now underway in Kuwait.
Saudi Arabia, the UAE and other Arab countries intervened in the war in March 2015 in support of the government, which had been swept into exile by the Houthis.
The US military announced last week it had deployed a small number of personnel to Yemen to aid in the fight against Al Qaeda in the Arabian Peninsula (AQAP) its first troop presence in the country since the Houthi takeover.