In a statement released on Friday, Mr. Guterres expressed his condolences to the families of those who lost their lives in the attack and wished a swift recovery to the injured.
The attack took place in the port city of Kismayo where, according to media reports, a suicide bomber drove a car containing explosives into the Asasey hotel. Gunmen then stormed the building.
The terror group al-Shabab has reportedly claimed responsibility for the attack, which is believed to have led to the deaths of at least 26 people, making it the worst to hit Kismayo since al-Shabab was forced out of the city in 2012.
The killings took place around 4 months after al-Shabab set off two car bombs in the Somali capital of Mogadishu, reportedly killing more than 20 people, and injuring scores more.
The Secretary-General reaffirmed the support and solidarity of the United Nations with the people of Somalia in their pursuit of a peaceful future.