The attack started with what is assumed to have been a suicide auto bomb detonated outside the Nasa-Hablod 2 Hotel near the presidential palace in Mogadishu.
Police Officer Ali Mohamed told Anadolu Agency over the phone that a vehicle bomb had targeted the Nasa-hablood hotel near the presidential palace; soon after another auto bomb exploded near the scene.
That attack also began when a suicide bomber detonated an explosives-laden vehicle outside the hotel which was then stormed by gunmen, provoking an assault that lasted several hours and only ended when special forces killed three attackers inside.
Initial reports say at least 10 people were killed in the first explosion and 6 others were injured.
The second auto bomb exploded near the former parliament building, and the extent of damage caused by the second explosion is not yet clear.
"Security forces have entered a small portion of the hotel building ... the exchange of gunfire is hellish", he said.
The police personnel who died had been stationed close to hotel's gate.
"We can confirm that the president was not at the hotel at the time of the attack", he said.
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One senior police official and a former MP are among the dead. Sporadic gunfire could be heard in the vicinity.
"We can hear the gunfire but it is hard to know who is fighting, the forces cordoned off the building and no one can go close to it", said Abdulahi Nure.
Witnesses in some previous attacks have said al-Shabab fighters disguised themselves by wearing military uniforms.
He said the hotel belonged to Somalia's internal security minister, Mohamed Abukar Islow.
Somali-based insurgent group al-Shabaab claimed responsibility for the attack and said its fighters remain inside the hotel.
The twin attack came just two weeks after a massive truck bomb exploded in central Mogadishu, killing at least 358 people, making it the deadliest attack in the troubled country's history.
Three of the five attackers were killed, Capt Hussein said.