Yemen's President Ali Abdullah Saleh (photo: Reuters)
The danger from Al-Qaeda's branch in Yemen, whose leader has vowed to avenge Osama bin Laden's killing, would increase if the regime of embattled President Ali Abdullah Saleh falls, analysts say.
"The threat of Al-Qaeda in the Arabian Peninsula [AQAP] should be taken seriously. It has the largest capacity to inflict damage among Al-Qaeda groups," said Mustapha al-Ani, security and terrorism director at the Dubai-based Gulf Research Centre.
"AQAP would benefit from a fall of the regime to reinforce logistically and increase its numbers" in Yemen, the scene of 15 weeks of deadly protests demanding the departure of Saleh, he said.
The local franchise of the jihadist network was born out of a merger of the Saudi and Yemeni branches in 2009, and it is active mainly in the south and east of the impoverished Arabian Peninsula country.
The Yemeni chief of AQAP, Nasir al-Wahishi, threatened in a message released on Wednesday to intensify attacks to avenge bin Laden's killing by US commandos on 2 May near the Pakistani capital.
"What is coming is greater and worse, and what is awaiting you is more intense and harmful," he vowed.
AQAP has some 1,000 fighters, mostly Yemenis, and "benefits from the chaotic situation in Yemen which helps in strengthening its position in the society," said Dominique Thomas, a Paris-based specialist on Middle East Islamist groups.
The group has managed to "weave alliances with tribes," Thomas said. "AQAP could benefit from instability which would result in its control over certain areas in Yemen."
The group was behind an attempt to bomb a US-bound flight from Amsterdam on Christmas Day in 2009, and has claimed responsibility for explosive parcels that were intercepted in October in Dubai and Britain en route to the United States.
"With such operations, AQAP has proven capable of launching attacks at a distance and has formed cells in Western countries," said Saeed Obeid al-Jihmi, a Yemeni specialist in Islamist organisations.
"Taking advantage of the deterioration in security and the defections in the Yemeni army, AQAP has reinforced its ranks by attracting more fighters and sympathisers," he said.
"The group could strike at any time to prove that the extremist network remains alive" despite the elimination of bin Laden, he added.
Wahishi's threat to avenge the killing of bin Laden, whose Saudi family descended from Yemen, "should be taken seriously," according to Jihmi.
"AQAP is not (just) threatening. It is telling what it will do," said Jihmi, author of Al-Qaeda in Yemen, published in 2008. "Its response to the killing of bin Laden will be hard."
Bin Laden's body was buried at sea hours after a 2 May operation in which US special forces in helicopters flew under Pakistani radar cover and raided a house in the northwestern garrison town of Abbottabad, near Islamabad.
The United States, which views Saleh as an ally in its "war on terror," has warned of the threat posed by Islamist militancy in Yemen and repeatedly voiced concern over the country's potential to become a new staging ground for Al-Qaeda.