SANAA - A suicide bom-ber blew up a vehicle outside a presidential palace in southeastern Yemen Saturday, killing 26 elite troops and overshadowing the swearing in of the first new president in Sanaa since 1978.

A military official said the bombing in the Hadramawt provincial capital Mukalla bore the hallmark of Al-Qaeda, as Abdrabuh Mansur Hadi pledged after taking the oath to succeed veteran strongman Ali Abdullah Saleh that he would press the battle against the jihadists.

Militants loyal to Al-Qaeda have exploited the decline in central government control that accompanied 10 months of deadly unrest that led up to Saleh’s agreement to cede power to seize large swathes of southern and eastern Yemen.

“A pick-up truck driven by a suicide bomber exploded at the entrance of the presidential palace in Mukalla,” the military official said.

He said the attack “carries the fingerprints of Al-Qaeda,” adding that the bomber “could be Mohammed al-Sayari,” a Saudi originally from Hadramawt.

“The bodies of 20 soldiers were taken to the mortuary and there are many others wounded,” said a medic at Mukalla’s Ibn Sina hospital.

Another medic said later that “six others have died of their wounds.” The military source said 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 Saleh’s son Ahmed and who played a key role in the veteran strongman’s deadly crackdown on the uprising against his rule before finally signing November’s transfer of power deal.

In an address to the nation straight after being sworn in to succeed Saleh, Hadi vowed to press the fight against Al-Qaeda and restore security across his impoverished nation, ancestral homeland of slain jihadist leader Osama bin Laden.

“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.”

Hadi said he had the political legitimacy to meet the huge challenges facing the country after winning overwhelming endorsement in a Tuesday election in which his name was the only one on the ballot paper.

He vowed to “turn a new page in the building of a new Yemen which unites all its citizens.”

Official results released late Friday gave Hadi 99.8 percent of valid votes cast in the election in which turnout reached 60 percent nationwide.

But in a sign of the country’s divisions, the turnout was by no means uniform. In the formerly independent south, from which Hadi himself hails, it was less than 40 percent in most provinces in the face of attacks on polling stations by secessionist militants. In the far north where Zaidi Shiite rebels called for a boycott, it was also below 50 percent.

The Mukalla bombing was followed by an exchange of fire between the soldiers and gunmen, the military official said. Residents of the city told AFP gunfire was heard from the area around 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.

Saturday’s parliamentary swearing-in is to be followed by a ceremony at the presidential palace in Sanaa on Monday at which the veteran strongman is to formally hand over the reins of power to Hadi.

Saleh, who has been receiving treatment in the United States, flew into Sanaa earlier Saturday urging Yemenis to give their support to his successor.

He told Al-Jazeera television the new president needed their backing to “rebuild the country” and “deal with the consequences of the crisis which has shaken it for the past year.”

Under the UN-backed Gulf-brokered transfer of power deal, Hadi is to serve as president for an interim period of two years, after which there will be a contested presidential election along with parliamentary polls.

During that period, Saleh is to remain at the helm of his General People’s Congress party, stoking suspicions within the protest movement that he has not finally renounced his long grasp on power.

“Nothing in the Gulf countries’ initiative prevents him from being a candidate (to return as president) in two years, even if he says he has bid farewell to power,” the party’s spokesman, Deputy Information Minister Abdo Janadi, said on Wednesday.