The death toll from a suicide attack inside the mayor’s office of Somalia’s capital has risen to 11, authorities said, adding that the injured mayor has been sent abroad for treatment.

At least six people were originally reported to have been killed in Wednesday’s attack that took place just hours after a visit by the newly appointed United Nations envoy.

Three local district commissioners were among the dead, police officer Ahmed Bashane told the dpa news agency on Thursday. Local media reported that Mayor Abdirahman Omar Osman and four other local government officials had been airlifted to Qatar for treatment.

Al-Shabab, an al-Qaeda-affiliated group claimed responsibility for the attack, telling local media that UN envoy to Somalia James Swan, who had left the building when the attack happened, was their target.

190724144311162

Captain Mohamed Hussein, a senior police officer, said a female bomber walked into a security meeting and blew herself up a few yards away from the mayor in what was the fourth known time al-Shabab has used a woman in a suicide attack.

In a statement following the attack, Swan condemned the “heinous attack which not only demonstrates a violent disregard for the sanctity of human life, but also targets Somalis working to improve the lives of their fellow Somalis”.

The United States ambassador to Somalia, Donald Yamamoto and UN Secretary-General Antonio Guterres also condemned the attack.

.@UN envoy to #Somalia James Swan condemns today's attack in offices of #Mogadishu’s Mayor @engyarisow, whom he had met earlier in the day. “The UN stands with the people and government of Somalia… and our thoughts are with the victims.” For more: https://t.co/nroqPECKEX pic.twitter.com/w1FhCnuzCb — UNSOM (@UNSomalia) July 24, 2019

It was not clear how the bomber gained access to the mayor’s offices as visitors are required to pass through at least four metal detectors, according to the AFP news agency. Some security officials said the attacker might have coordinated with corrupt officials, offering them bribes for access.

Al-Shabab has been fighting to topple Somalia’s fragile government since 2007. The government is backed by a 20,000-strong African Union force – AMISOM – and the UN.

The group regularly launches attacks on government buildings and hotels in the volatile country in the Horn of Africa.