Gunmen killed 20 Yemeni soldiers in a dawn attack on a checkpoint Monday, most of them in their sleep, in the latest in a wave of deadly violence blamed on Al-Qaeda.
The assault came in the eastern province of Hadramawt were the security forces have suffered repeated losses which prompted President Abdrabuh Mansur Hadi to fire his interior minister earlier this month.
"Twenty soldiers were killed in the armed attack on an army checkpoint" near Reida, 135 kilometres (85 miles) east of the provincial capital Mukalla, the official Saba news agency reported.
The assailants drove up to the checkpoint in a convoy of vehicles, raking the soldiers on duty with automatic weapons before hurling grenades at an adjacent tent where the majority of the contingent were asleep, a military source told AFP.
The attack "bore all the hallmarks of Al-Qaeda," the source added.
The global jihadist network's Yemen branch, Al-Qaeda in the Arabian Peninsula (AQAP), is viewed by Washington as its most dangerous and has claimed repeated deadly attacks, some of them in the heart of the capital Sanaa.
A military helicopter landed at the scene of the attack in the middle of the day to recover the bodies of the slain soldiers while a fighter aircraft patrolled overhead, witnesses said.
New Interior Minister Abdo Tareb ordered the province's security chief General Fahmi Mahrus and its special forces commander detained for questioning over how the attackers had been able to overwhelm the checkpoint, Saba added.
Tareb was appointed on March 8 when President Abdrabuh Mansur Hadi fired his predecessor Abdelqader Qahtan for failing to improve the "below-par" performance of the security forces.
Despite repeated attempts by the army to crush AQAP in its strongholds in the east and south, its militants have carried out repeated deadly attacks on the security forces.
On March 18, a suspected Al-Qaeda suicide bomber blew up a vehicle at a military intelligence headquarters outside the southern port city of Aden, killing a guard and wounding 13 others.
The attack came two days after three suspected Al-Qaeda militants, one a Saudi, were killed in the southern province of Shabwa when a car bomb they were preparing apparently detonated prematurely.
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- Intensified drone campaign -
Residents of Reida said they had heard US drones flying over the area in the two days before the attack on the checkpoint, although there had been no strikes.
The United States has launched repeated drone strikes on Al-Qaeda targets in Yemen in support of the army's campaign against the jihadists.
Dozens of militants have been killed in a sharply intensified campaign over the past year.
A Friday drone strike in Al-Jawf province in the northeast killed a local Al-Qaeda commander and his bodyguard, a tribal source said.
The drone war has triggered criticism from human rights activists, who say it has also killed many innocent civilians.
The United Nations said 16 civilians were killed and at least 10 wounded when two separate wedding processions were hit in December.
The victims had been mistakenly identified as members of Al-Qaeda, the UN quoted local security officials as saying at the time.
Following the deaths, the Yemeni parliament voted for a ban on drone strikes, but lawmakers have limited powers over security policy.
The United States says that use of the unmanned aircraft is an essential part of its "war on terror".
AQAP took advantage of a weakening of central government control during a 2011 uprising that forced veteran president Ali Abdullah Saleh from power to seize large swathes of southern and eastern Yemen.
The army has since regained control of most of the region's main towns but the jihadists remain active in the countryside.