One attacker drove his bomb-laden truck into a checkpoint in a western district of Hadramawt's provincial capital Mukalla, security officials told AFP.
The second attacker simultaneously blew up his vehicle at an army checkpoint in the nearby town of Hajr, located some 15 kilometres to the west of Mukalla, the sources said.
The commander of Hadramawt's second military region, General Faraj Salmeen had earlier told AFP that the second bombing struck the centre of the city, blaming the attack on "terrorists".
Four civilians were among those killed, he told AFP.
More From This Section
No group has yet claimed responsibility.
Mukalla and surrounding towns were under the control of Al-Qaeda for one year until pro-government troops backed by a Saudi-led coalition recaptured the city in April.
In March, a US air strike on an Al-Qaeda training camp in Hajr killed more than 70 jihadists, provincial officials said.
Yemen has been gripped by a devastating conflict that escalated in March 2015 when Saudi-led air strikes began against Iran-backed Huthi rebels after the insurgents seized northern and central parts of the country including the capital, Sanaa.
Last month, IS claimed a wave of suicide bombings targeting Yemeni troops in Mukalla that killed at least 42 people.
The Pentagon said in May that a "very small number" of US military personnel had been deployed around Mukalla in support of pro-government forces.
Washington considers the Yemen-based Al-Qaeda in the Arabian Peninsula to be the network's deadliest franchise and its drone strikes have taken out a number of senior AQAP commanders in Yemen over the past year.