A suicide bomber on Monday killed the army general spearheading a blistering offensive against Al-Qaeda in south Yemen, throwing himself on the officer's vehicle as he blew himself up, officials said.
President Abdrabuh Mansur Hadi blamed Al-Qaeda for the attack and vowed to "cleanse the country from the evil of terrorists," the official Saba news agency reported.
The attack on General Salem Ali Qoton came as Al-Qaeda fled its last bastion in Yemen's restive southern and eastern provinces in the face of the military's month-long withering assault aimed at destroying the jihadist network.
Qoton, chief military commander in south Yemen, was attacked while on his way to his office in the port city of Aden, witnesses said.
According to a report on Yemen's defence ministry website, a military official said the bomber, a "Somali national ... threw himself on (Qoton's)' vehicle and then detonated his explosives," as the general drove through Aden's Mansura neighbourhood.
Speaking on condition of anonymity, the official said the explosion "killed the general and two of his aides."
A medic related to Qoton said the attacker brazenly shook hands with the general before blowing him up.
The medic, speaking on condition of anonymity, said the attacker "handed Qoton a paper, shook his hand and then detonated himself," when the general was walking to his office.
President Hadi said the bombing was carried out by "the defeated terrorist Al-Qaeda elements."
Hadi also vowed to "continue to cleanse the country from the evil of terrorists and maintain security and stability," Saba reported.
No one has claimed responsibility for the attack.
As chief commander, Qoton has led the offensive against Al-Qaeda, forcing the militant group to withdraw from a string of towns and villages in Abyan and Shabwa provinces which they had controlled since last year.
Late Sunday, Al-Qaeda fled from their last bastion in the town of Azzan in Shabwa province, the last town in Yemen where they had established complete control, the town's deputy mayor said.
Yaslam Bajanoub said that the jihadists "handed over the city late Sunday night to a committee of tribal mediators."
Al-Qaeda had declared an Islamic emirate in the desert town where hundreds of fighters are believed to have sought refuge after fleeing their strongholds in Abyan which fell to army control last week.
Bajanoub said the jihadists also fled the neighbouring village of Al-Huta, adding that the army was likely to "enter Azzan in the coming days."
In the past week, Al-Qaeda has also withdrawn from their three main strongholds in Abyan, including the capital Zinjibar and the towns of Jaar and Shuqra.
The group's fighters are believed to have retreated to safe havens in the country's mountainous regions in Shabwa, Marib and Hadramawt provinces where they enjoy tribal protection.
Qoton was appointed in March just days after newly elected Hadi took office with a pledge to destroy Al-Qaeda in the Arabian Peninsula, the name given to the militant group's local Yemen branch.
The post had been held for decades by General Mahdi Maqola, known for his close ties to former president Ali Abdullah Saleh.
Saleh was accused by his opponents of allowing Al-Qaeda to establish a stronghold in Yemen's mostly lawless south and east.
Qoton's appointment was in line with the Gulf sponsored power-transition deal that saw Saleh quit after 33 years in power, and required Hadi to restructure the Yemeni army during a two-year interim period.
Ali Mansur, a senior army commander and close aide to Qoton described the general's death as "a huge loss for Yemen and its efforts to fight Al-Qaeda."
"In just three months, Qoton achieved major progress towards chasing down and eliminating" the militants from their strongholds, said Mansur, adding that the attack "bears the hallmark of Al-Qaeda."
In a separate incident Monday, Shabwa's governor, Hasan al-Ahmad, escaped an assassination attempt, tribal sources told AFP, adding that two soldiers and a civilian were hurt.
Hasan al-Ahmad was travelling with a convoy of soldiers on route from the provincial capital Ataq to Azzan when they came under attack.
The sources said two soldiers and a civilian were killed in the assault but the governor escaped unharmed.
Yemen's military launched its anti-Qaeda offensive on May 12.
A total of 567 people have already died in the campaign -- 429 Al-Qaeda militants, 78 soldiers, 26 militiamen and 34 civilians -- according to an AFP tally compiled from various sources.