MOGADISHU, Somalia — A Christmas dinner at the African Union peacekeeping base here was ambushed by Islamist gunmen and suicide bombers on Thursday, turning a festive respite into a bloody battleground that left at least five attackers dead.  The attackers, members of the militant group Shabab, Somalia’s Qaeda affiliate, sneaked into the base in the Somali capital, Mogadishu, evading security just as officers were eating, said Col. Ali Houmed, a spokesman for the African Union Mission in Somalia.  Colonel Houmed said in an interview that Somali and African Union security troops killed three of the assailants, two others detonated their explosives and two to three were still hiding on the premises, surrounded.  He said that the assailants had planned to terrorize the base but that “the situation is under control now.”  It was not immediately clear how the assailants had penetrated the heavily fortified base or whether any of the defenders or residents were hurt or killed. The base houses United Nations offices and some foreign embassies.  Still, it seemed clear that the assailants had picked an opportune moment for the ambush, appearing to know in advance that security might be less stringent than usual on Christmas Day, when foreign inhabitants would be celebrating.  Residents nearby heard heavy explosions and sporadic gunfire inside the base.  Asked how the assailants could have sneaked past the heavy security cordon that surrounds the base, Colonel Houmed said he was asking himself the same question.  “It’s another story, and an investigation will be launched,” he said.  The Shabab claimed responsibility for the assault, saying their fighters had targeted the Christmas festivities at the base.  Once one of Al Qaeda’s most powerful and feared franchises, ruling big swaths of Somalia, the Shabab have been in retreat for months, pushed back by African Union peacekeepers, defections and an increasingly hostile populace. An American airstrike in September killed Ahmed Abdi Godane, the Shabab’s leader, leaving the group in further disarray.  Still the Shabab remain dangerous, unpredictable and bold, known for audacious and chilling attacks. Their fighters routinely target the Somali government in Mogadishu. The group has also sought to terrorize neighboring Kenya, where many Somali refugees have fled over the years.  This month, Shabab attackers seized dozens of Kenyan miners, separated the Christians from the Muslims and executed the Christians, the Kenyan authorities said. Last month Shabab attackers hijacked a Kenya bus, pulled out the Christian passengers and executed them.  Rick Gladstone contributed reporting from New York.
At least five assailants were killed in the ambush, which began just as African Union officers were enjoying a Christmas Day respite.