If there’s any country ripe for an al-Qaeda takeover it’s Yemen.

SANAA (Reuters) – Dozens of Saudi Islamist militants have left the battlefields of Syria and Iraq for Yemen, where their experience appears to have contributed to a spate of lethal al Qaeda attacks, a senior Yemeni security official said.

The influx detected in the last few months is worrying for Yemen, a turbulent country where several hundred Saudi militants are already thought to be fighting alongside their Yemeni counterparts in al Qaeda in the Arabian Peninsula (AQAP).

The initial core of Saudis fled to Yemen after the kingdom defeated a violent al Qaeda campaign between 2003 and 2006, helping to create AQAP with their Yemeni comrades in 2009.

“Now the Saudi who comes here is an experienced fighter from the war in Iraq or Syria and is ready to be ‘martyred’,” said the Yemeni security official, who asked not to be named.

“They know how to build weapons and bombs, and they are teaching others.”

Foreign militants have flocked to Syria to join Islamist rebels battling President Bashar al-Assad in the last two years. Iraq had previously served as a magnet for global jihadis eager to fight U.S. forces and the Shi’ite-led authorities which came to power after the 2003 invasion that toppled Saddam Hussein.

Yemen is also a jihadi battleground where U.S. drone strikes have targeted al Qaeda leaders for more than a decade.

AQAP is not short of bomb-making expertise itself, as it has shown in bomb plots against Saudi and Western targets.

These include an attempt by a Nigerian to blow up a Detroit-bound airliner in 2009 with a bomb concealed in his underwear and a foiled plot to send two air freight packages containing bombs to the United States in 2010.