The head of Somalia's Olympic committee and its football chief are among eight people killed in a bomb attack on a high-profile event in Mogadishu.Prime Minister Abdiweli Mohamed Ali survived the blast unhurt after it struck the newly re-opened national theatre in the capital, Mogadishu.Militants from the al-Shabab group say they carried out the bombing.African Union peacekeepers said the "despicable" attack would not deter peace efforts in Somalia.The President of the Somali Olympic Committee, Aden Yabarow Wiish, and the Somali Football Federation chief, Said Mohamed Nur, were both killed. They were among a group of dignitaries who had gathered to mark the first anniversary of the launch of Somalia's national television station.Sepp Blatter, president of football's governing body Fifa, said he was shocked at the deaths of the sport officials."I knew both men personally and can only say good things about their endless efforts to promote sport and football in their country," he said in a statement. "They will be sorely missed."Three Somali television journalists were also wounded in the blast, sources told the BBC Somali Service.The theatre had closed in the early 1990s as Somalia descended into civil war and was only reopened last month, amid a new period of relative optimism.'Unimaginable' scenePolice and hospital sources told BBC News in Mogadishu that eight people had been killed.Also speaking to the BBC, the prime minister said a woman suicide attacker had carried out the attack.Condemning al-Shabab, he said it was in the group's nature to "kill innocent people" and described the attacks as "the last breaths of a dying horse".Abdullahi Yussuf Abdurahiman, 22, survived the explosion. He told BBC News: "I saw mutilated bodies, shoes on the ground, bloody mobile phones and chairs cut in half by the force of the blast."A lot of people were being carried out and there were dead people on the floor. It was unimaginable. Then everyone was running away."Soldiers started shooting after the blast, witnesses said.In a statement al-Shabab said it was behind the bombing but referred to a planted device rather than a suicide bomber."The Mujahideen successfully planted the explosives before the gathering," it said on Twitter.Al-Shabab spokesman Sheikh Abdiasis Abu Musab told Reuters news agency: "We were behind the theatre blast. We targeted the infidel ministers and legislators, and they were the casualties of today."The explosion comes as the UN-backed government seeks to show it has re-established control of the city since al-Shabab was forced out in August.However, al-Shabab has continued to attack the capital with bombs and mortars.Last week, African Union (AU) troops said they had seized control of territory on the outskirts of Mogadishu which, they said, had allowed the Islamist fighters to launch their frequent attacks on the city.Appeal for informationBrigadier General Audace Nduwumunsi, deputy commander of the AU mission said the peacekeepers stood firmly with the Somali government."Yet again the terrorists' methods show that they are enemies of peace and are foreign to Somali culture," he said."By their attack they are trying to derail the hopes and dreams of the Somali people but they will fail."He encouraged people in Mogadishu to come forward with any information about possible further attacks.