The death count has steadily risen since Saturday, when the blasts struck at two busy junctions in the heart of the capital city. One truck bomb detonated near a fuel truck, creating an enormous fireball.
The bomb attacks were the deadliest since Islamist terrorist group al Shabaab began an insurgency in 2007. Al Shabaab has not claimed responsibility, but the method and type of attack - a large truck bomb - is increasingly used by the al Qaeda-linked organisation.
"We have confirmed 300 people died in the blast. The death toll will still be higher because some people are still missing," Abdikadir Abdirahman, the director of the city's ambulance service, told Reuters.
Aden Nur, a doctor at the city's Madina hospital, said they had recorded 258 deaths and that 160 of the bodies could not be recognised.
"(They)were buried by the government yesterday. The others were buried by their relatives. Over a hundred injured were also brought here," he told Reuters at the hospital.
Some of the injured were being evacuated by air to Turkey for treatment, officials said.
Locals visiting their injured relatives or collecting their bodies filled every available space in Madina hospital.
"My last time to speak with my brother was some minutes before the blast occurred," Halima Nur, a local mother, told Reuters.
"I am afraid he was among the unrecognized charred bodies that were buried yesterday. I have no hope of getting him alive or dead. But I cannot go home."
Abdullahi Aden, 56, said five of his cousins had died.
DEADLIEST SINCE INSURGENCY BEGAN
Al Shabaab stages regular attacks in the capital and other parts of the country. Although the group claims it targets the government and security forces, it has detonated large bombs in crowded public areas before.
It has sometimes not claimed responsibility for bombings that provoked a big public backlash, like the 2009 suicide bombing of a graduation ceremony for medical students.
The group is waging an insurgency against Somalia's U.N.-backed government and its African Union allies in a bid to impose its own strict interpretation of Islam.
The terrorists were driven out of Mogadishu in 2011 and have been steadily losing territory.
But Al Shabaab retains the capacity to mount large bomb attacks. Over the past three years, the number of civilians killed by insurgent bombings has steadily climbed as al Shabaab increases the size of its bombs.
In 2016, 723 Somalis were killed in 395 bomb attacks, according to Nairobi-based thinktank Sahan Research, up from 193 deaths in 265 attacks in 2015.
Some of those seriously injured in Saturday's bombing were moved by ambulance to the airport on Monday morning to be flown to Turkey for further treatment.
Workers unloaded boxes of medicine and other medical supplies from a Turkish military plane and Turkish medical teams attended to the injured moved from the hospital for evacuation.
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