A suicide bomber blew up a vehicle outside a presidential palace in southeastern Yemen on Saturday, killing 26 elite troops and overshadowing the swearing in of the first new president in Sanaa since 1978, medics and a military official said.
"The bodies of 20 soldiers were taken to the mortuary and there are many others wounded," a medic had said at the Ibn Sina hospital in the Hadramawt provincial capital Mukalla.
Another medic said later that six others have died of their wounds.
A military official said that "a pick-up truck driven by a suicide bomber exploded at the entrance of the presidential palace in Mukalla" as Abdrabuh Mansur Hadi took the oath of office as president in the capital.
The official said the attack "carries the fingerprints of Al-Qaeda," adding that the attacker "could be Mohammed al-Sayari," a Saudi who is originally from Hadramawt.
The same source said that no high-ranking officials were in the palace when the bomber struck.
The palace is guarded by troops of the elite Republican Guard, who are under the command of outgoing president Ali Abdullah Saleh's son Ahmed.
The bombing was followed by an exchange of fire between the soldiers and gunmen, the military official said.
Mukalla residents told AFP that gunfire was heard from the area surrounding the Ibn Sina hospital as a medic said that Republican Guard troops were turfing out civilian patients to make room for their wounded.
"Republican Guard troops have surrounded the hospital to guard their men," the military official said.
In an address to the nation straight after being sworn in to succeed Saleh, Hadi had vowed to press the fight against Al-Qaeda and restore security across his impoverished nation.
"It is a patriotic and religious duty to continue the battle against Al-Qaeda," the new president said.
"If we don't restore security, the only outcome will be chaos."