A celebrated Canadian-Somali journalist Hodan Naleyah also succumbed in the incident.
He said 56 people were wounded in the attack, including two Chinese citizens.
The attack began Friday night with a suicide auto bomb at the entrance gate and continued with an assault by gunmen who stormed into the building, which is frequented by politicians, patrons and lawmakers.
Jihadist group al-Shabab immediately claimed the responsibility for the attack through al-Andalu Radio, the group's FM station.
"First, we targeted the hotel with a suicide auto bomb and then armed mujahideen stormed the hotel".
The attack is a blow to the Somalian government's efforts to hold nationwide one-person one-vote elections next year.
A Somali security official told local media that the operation of ending the attack was over at 7 am on Saturday.
Al-Shabaab, which is an official affiliate of al-Qaida, has been waging a war for more than a decade to overthrow Somalia's western-backed central government and install its own rule based on its strict interpretation of sharia law.More news: Manchester United coach Mark Dempsey will return to UK following hospital stay
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SADO Somalia, a local non-governmental organisation, said its executive director Abdullahi Isse Abdulle had died in the attack.
"Mohamed Omar Sahal, SBC TV correspondent based in Kismayo and Hodan Naleyeh, female TV journalist and founder of Integration TV [are] both among [those] killed", Abdalle Ahmed Mumin, the syndicate's secretary general, said. What a loss to us.
"Through her work as a journalist, Hodan highlighted the community's positive stories and contributions in Canada".
The victims included several foreigners and a prominent Somali-Canadian journalist, Nodan Halayeh, who perished along with her husband.
Canadian politician Andrea Horwath reacted to the experiences of Nalayeh's demise on Twitter, asserting her "never-ending positivity and her delight in for of us became once inviting". We are deeply saddened by the bad loss of one of our colleagues Abdifatah Mohamed Abdow who dedicated his work to Somalia.
"So far we know 26 people died".
The U.S Mission to Somalia issued a statement Saturday morning, vowing to work with local and global leaders in the aftermath of the attack. "Somalia has made tremendous progress in seizing territory and pushing out the terrorists from many places across the country".
The chairperson also reiterated "the firm and continued solidarity of the African Union with the people of Somalia in their pursuit for peace in their country".