FACTBOX: Qaeda's resurgent Gulf wing stirs security fears

(Reuters) - Resurgent al Qaeda attacks have stirred fears of worsening instability in Yemen, an impoverished country struggling with multiple security threats, and a resumption of militant violence in neighboring oil superpower Saudi Arabia.

Here are some facts about the group behind the attacks, al Qaeda in the Arabian Peninsula (AQAP).

* Al Qaeda's wing in Yemen, where Osama bin Laden's father was born, announced in January it had changed its name to al Qaeda in the Arabian Peninsula. The move was an apparent attempt to revive the group in Saudi Arabia, where its activities had been halted in 2006 by a vigorous counter-terrorism drive.

* In the video announcement, the new group's leader, Abu Basir Nasser al-Wahayshi, a Yemeni, threatened attacks against Westerners in the oil-exporting region. The group has also called for the overthrow of the U.S.-allied Saudi royal family.

* The group claimed a suicide attack that killed four South Korean tourists in March, in retaliation for their country's ties to the U.S.-led "war on terror," as well as mortar attacks on foreign embassies and housing compounds in Yemen last year.

* On Aug 27, Abdullah al-Asiri, a 23-year-old AQAP suicide bomber posing as a repentant militant, tried to kill the Saudi prince who heads the kingdom's anti-terrorism campaign. It was the first attack on a royal family member since al Qaeda began a wave of violence in 2003. Saudi media said the bomber had hidden the device in his rectum -- security experts say there is no routinely-deployed technology to guard against such a method.

* The incident confirmed Saudi fears that Yemen has become a new center for al Qaeda, where many Saudis on a list of 85 wanted militant suspects are thought to be. An insurgency in the north and separatist unrest in the south has created instability that al Qaeda can exploit, Saudi officials fear.

* The United States shares those fears and is reluctant to repatriate the 97 Yemenis still detained in Guantanamo Bay, Cuba, in case they are released and resume militant activity. Two Saudi former Guantanamo inmates joined AQAP in Yemen early this year, although one subsequently returned to Saudi Arabia.

* On November 1 Wahayshi, the AQAP leader, urged militants to attack airports and trains in the West, saying they could make bombs from household materials. He has also called for attacks on countries fighting wars in Muslim states.

* CTC Sentinel, a U.S.-based publication that researches militant affairs, has said al Qaeda may be trying to forge alliances with Yemeni tribes through marriages.

* Among recent attacks, the group claimed responsibility for the November 3 killing of seven Yemeni security officials in an ambush near the Saudi border.

* Gulf states hope that a border fence Saudi Arabia is building can end infiltration, especially from the 1,500 km (940 mile) border with Yemen, the poorest country in the region.

(Writing by William Maclean; Editing by Alistair Lyon and Jon Hemming)