Suicide bomber rammed a vehicle loaded with explosives into the Medina hotel

At least 26 people, including several foreigners, were killed and 56 injured in a suicide bomb and gun attack claimed by Al-Shabaab militants on a popular hotel in southern Somalia, a top regional official said on Saturday.

A suicide bomber rammed a vehicle loaded with explosives into the Medina hotel in the port town of Kismayo on Friday before several heavily armed gunmen forced their way inside, shooting as they went, authorities said.

The siege lasted for almost 12 hours and only ended on Saturday morning after clashes with security forces.

Three Kenyans, three Tanzanians, two Americans, one British and one Canadian were among the 26 people killed in the attack, president Ahmed Mohamed Islam of the semi-autonomous Jubaland region told a news conference.

"There are also two wounded Chinese citizens," he added.

AFP confirmed with family members that at least four of the dead had dual nationality.

"The security forces are in control now and the last terrorist was shot and killed", Mohamed Abdiweli, a security official, said.

"There are dead bodies and wounded people strewn inside the hotel," Abdiweli said.

He said authorities believed four gunmen, who one witness described as wearing Somali police uniforms, were involved in the attack.

Shabaab, the Al-Qaeda-linked group, claimed responsibility for the siege describing it as "a martyrdom attack"

"There is chaos inside, I saw several dead bodies carried from the scene and people are fleeing from the nearby buildings," witness Hussein Muktar said during the assault.

"The blast was very big," he added.

The attack is the latest in a long line of bombing and assaults claimed by Al-Shabaab.

Witnesses said among those killed were a well-known social media activist and a local journalist.

"The relatives of local journalist Mohamed Sahal confirmed his death and I'm getting that social media activist Hodan Naleyeh and her husband also died in the blast," witness Ahmed Farhan said.

The Somali journalists' union SJS confirmed the reporters' deaths. "It is a very sad day for Somalian journalists," the union's secretary-general Ahmed Mumin said in a statement.

According to several sources, most of those staying in the hotel were politicians and traders ahead of upcoming regional elections.

"The whole building is in ruins, there are dead bodies and wounded who have been recovered from inside. The security forces have cordoned off the whole area," said witness Muna Abdirahman.

Shabaab fighters have fought for more than a decade to topple the Somali government.

The militant group emerged from Islamic Courts that once controlled central and southern Somalia and are variously estimated to number between 5,000 and 9,000 men.

In 2010, the Shabaab declared their allegiance to Al-Qaeda.

In 2011, they fled positions they once held in Mogadishu, and have since lost many strongholds.

But they retain control of large rural swathes of the country and continue to wage a guerrilla war against the authorities.