Mogadishu - At least 31 people are dead after the overnight siege of a popular restaurant in Somalia's capital by al-Shabaab Islamic extremists, ended on Thursday morning by security forces with all five attackers killed. Police said many victims were killed at point-blank range after being hunted down.Survivors described harrowing scenes of hiding under tables and behind curtains as attackers searched for patrons in the darkened Pizza House restaurant, firing their weapons."I never thought I would have the chance to see the sun again. They were killing people on sight," Saida Hussein, a university student, told The Associated Press. She said she survived by hiding behind a large table.Al-Shabaab claimed responsibility shortly after the assault began on Wednesday night with a car bomb exploding at the restaurant's gate. Witnesses said gunmen posing as security forces in uniform then rushed in. The attackers cut off the electricity, complicating rescue efforts, police said.Soldiers surrounded the building and used vehicle-mounted guns to neutralize the attackers early on Thursday. Troops entered the ground floor while the extremist snipers held positions upstairs.All five attackers were killed and the soldiers secured the building after dawn, senior police Captain Mohamed Hussein said.Many of the 31 victims were killed at point-blank range, Hussein said. Nearly 40 other people were wounded.One survivor, Aden Karie, was wounded by an attacker who spotted him moving behind a curtain."He shot at me twice and one bullet struck me on the leg," Karie said as he was taken to a waiting ambulance.The bodies of five girls were found in the restaurant, police said. The body of a Syrian man who worked as a chef there lay near the rubble of a blood-spattered and bullet-marked wall.Wednesday night's car bomb blast tore the roofs off the restaurant and nearby buildings. Many of the first victims were young men who had been entering the restaurant when the vehicle exploded, Hussein said.The gunmen "were dressed in military uniforms. They forced those fleeing the site to go inside" the restaurant, witness Nur Yasin told the AP.While al-Shabaab claimed to have attacked the neighboring Posh Treats restaurant, which is frequented by the city's elite and was damaged in the blast, security officials said the Pizza House was targeted instead.Security forces rescued Asian, Ethiopian, Kenyan and other workers at Posh Treats as the attack unfolded, Hussein said.The Somalia-based al-Shabaab often targets high-profile areas of Mogadishu, including hotels, military checkpoints and areas near the presidential palace. It has vowed to step up attacks after the recently elected government launched a new military offensive against it.Al-Shabaab last year became the deadliest Islamic extremist group in Africa, with more than 4 200 people killed in 2016, according to the Washington-based Africa Center for Strategic Studies.The extremist group also faces a new military push from the United States after President Donald Trump approved expanded operations, including airstrikes, against al-Shabaab. On Sunday, the US military in Africa said it carried out an airstrike in southern Somalia that killed eight Islamic extremists at a rebel command and logistics camp.Somalia President Mohamed Abdullahi Mohamed confirmed that airstrike and said such attacks would disrupt the group's ability to conduct new attacks.With a new federal government established, pressure is growing on Somalia's military to assume full responsibility for the country's security. The 22 000-strong African Union multinational force, AMISOM, which has been supporting the fragile central government, plans to start withdrawing in 2018 and leave by the end of 2020..