UPDATE: 4:10 a.m. EDT — Al Arabiya, a Saudi-owned television network, reported 25 dead in the suicide bombing in Mukalla in southern Yemen. The Islamic State group, also known as ISIS, has claimed responsibility for the attack.

Social media users have posted videos of the aftermath of the blast, which shows people picking up and carrying bodies away from the scene.

Original story:

A suicide bomber blew himself up Sunday among a group of recruits who had gathered to register with local security forces in the southern Yemeni city of Mukalla, according to local media reports.

While a report by Reuters said several were killed, without giving any numbers, a report by Aden Tomorrow, a local media outlet, said at least six people had been killed and another 13 were injured.

Al Aan TV, a Dubai-based network, cited witnesses saying that dozens of civilians had died or were wounded in the attack which took place near the gate of the registration camp for the recruits.

Social media users posted pictures from the scene of the attack, and some put the death toll closer to 20.

Some other users also mentioned a second attack which targeted Brigadier Mubarak Alaobthani, security director for Hadramout province. Alaobthani reportedly survived the attack, but a number of his guards died.

Sunday’s blast was the second deadly one to hit Mukalla, which was a hub for al Qaeda till April, when security forces pushed the group out. The city is an important port in the country torn by a yearlong civil war which has already claimed about 6,300 lives.