At least eight people were killed when a car bomb rammed into one of Mogadishu's top hotels Wednesday and a second vehicle exploded as the wounded were being treated.
There was no immediate claim of responsibility but the attack, which also appeared to involve a commando of gunmen, bore all the hallmarks of Somalia's Al Qaeda-linked Shebab group.
"A booby-trapped car exploded against hotel Jazeera," near a United Nations complex, police officer Muhidin Ahmed told AFP. "It appears to be a suicide attack."
He was not immediately able to provide an accurate casualty toll for the first blast, but a witness spoke of at least five dead.
The second car bomb ripped through the blast scene as ambulances rushed in and Somali soldiers were helping the wounded.
"Another car loaded with explosives went off as security forces were trying to assist victims," police officer Mohamed Warsame said.
"I counted eight bodies, most of them soldiers," said witness Abdikarim Hassan.
The Jazeera hotel, near the international airport, is one of the seaside capital's most upmarket and its clientele includes Somali politicians and visiting foreign officials.
Eyewitnesses also reported an intense exchange of gunfire between assailants and security officers between the back-to-back blasts.
The attack was similar to others carried out by the Shebab in Mogadishu, with a first car bomb smashing through the well-guarded gates of a target to let in a suicide commando and sometimes another explosives-laden vehicle.
The Shebab claimed responsibility for a spectacular September onslaught on an upscale shopping mall in Nairobi that left at least 67 people dead.
The group said at the time the attack was retaliation for Kenya's military involvement in Somalia.
The Shebab once controlled most of southern and central Somalia but withdrew from fixed positions in Mogadishu two years ago.
African Union troops -- including large contingents from Uganda, Kenya and Burundi -- have since recaptured every major insurgent bastion and tried to prop up Somalia's fledgling government forces.
But a string of devastating Shebab attacks against foreign and government targets have shattered hopes of a rebirth for the war-ravaged capital and demonstrated that the Islamist outfit's disruptive power was undiminished.
The group, which has become a magnet for foreign jihadists, has carried out an average of one "complex attack" every six or eight weeks over the past year.
In 2013, devastating attacks were carried out in Mogadishu against the main courthouse, a UN compound, Turkish interests and an ambush also targeted the president's convoy.
Shebab insurgents also fought off a hostage-rescue attempt by French commandos a year ago.
The latest major attack came in mid-November in the central town of Beledweyne when a suicide car bomber blasted open a police compound before commandos entered and sprayed gunfire, killing 16.