At least 125 people were wounded, Aamin Ambulance service director Abdiqadir Abdulrahman said, and hundreds of Mogadishu residents donated blood in response to desperate appeals.
Mogadishu residents are donating blood to assist at least 125 people who were injured by a massive truck bomb attack.
The truck bomb exploded at a busy security checkpoint in Somalia's capital on Saturday morning, killing at least 79 people including many students, authorities said.
Two Turkish nationals are among the dead, Somalia's foreign minister said, and Turkish President Recep Tayyip Erdogan condemned the attack.
It was the worst attack in Mogadishu since the devastating 2017 bombing that killed hundreds
Aamin Ambulance service director Abdiqadir Abdulrahman said hundreds of Mogadishu residents have responded to desperate appeals to donate blood to save injured victims.
The explosion ripped through rush hour as Somalia returned to work after its weekend.
President Mohamed Abdullahi Mohamed condemned the attack as a “heinous act of terror" and blamed the local al Shabab extremist group, which is linked to al Qaeda and whose reach has extended to deadly attacks on luxury malls and schools in neighbouring Kenya.
Bodies lay on the ground amid the blackened skeletons of vehicles. At a hospital, families and friends picked through dozens of the dead, gingerly lifting sheets to peer at faces.
Most of those killed were university students returning to class and police officers, said Somalia's police chief General Abdi Hassan Hijar. He said the vehicle detonated after police at the checkpoint blocked it from proceeding into the city.
Somalis mourned the deaths of so many young people in a country trying to rebuild itself after decades of conflict.
There was no immediate claim of responsibility, but al Shabab often carries out such attacks.
Erdogan condemns 'terrorist attack'
"I condemn the terror attack in Mogadishu, I wish Allah's mercy upon two Turkish citizens and Somalian brothers who lost their lives and speedy recovery for those who were injured," Turkey's President Recep Tayyip Erdogan wrote on Twitter.
Offering his condolences to the Turkish nation and Somali people, Erdogan said: "Turkey always stands by Somalia."
"Treacherous terrorist attack killed two of our Turkish citizens along with our innocent Somalian brothers and sisters. I pray for God's mercy. We will always stand by our brothers in Somalia. Our struggle against terror will continue with determination," Turkish Foreign Minister Mevlut Cavusoglu said in a statement.
"Our airplane loaded with emergency aid equipment and material belonging to the Turkish Armed Forces departed from Kayseri in order to provide emergency aid to our Somalian brothers injured in the despicable terror attack in Somalia," the Turkish defence ministry said.
Al Shabab blamed
Al Shabab was pushed out of Mogadishu several years ago but continues to target high-profile areas such as checkpoints and hotels in the seaside city.
Al Shabab is now able to make its own explosives, its “weapon of choice,” United Nations experts monitoring sanctions on Somalia said earlier this year.
The group had previously relied on military-grade explosives captured during assaults on an African Union peacekeeping force.
Despite that advance in bomb-making, one security expert said the unlikely choice of target Saturday — a checkpoint at the western entrance to the capital — reflected al Shabab's weakening capability to plan and execute attacks at will. Mogadishu recently introduced tougher security measures that Somali officials said make it more difficult to smuggle in explosives.
“It feels like they literally knew that their (car bomb) may not proceed through the checkpoint into the city undetected, considering the additional obstacles ahead, so bombing the busy checkpoint in a show of strength appeared to be an ideal decision," the Mogadishu-based Ahmed Barre told AP.
Al Shabab was blamed for the truck bombing in Mogadishu in October 2017 that killed more than 500 people, but the group never claimed responsibility for the blast that led to widespread public outrage. Some analysts said al Shabab didn't dare claim credit as its strategy of trying to sway public opinion by exposing government weakness had badly backfired.
“This explosion is similar like the one ... in 2017. This one occurred just a few steps away from where I am and it knocked me on the ground from its force. I have never seen such a explosion in my entire life," witness Abdurrahman Yusuf said.
The attack again raises concern about the readiness of Somali forces to take over responsibility for the Horn of Africa country's security in the coming months from the AU force.
Al Shabab, the target of a growing number of US air strikes since President Donald Trump took office, controls parts of Somalia's southern and central regions. It funds itself with a “taxation” system that experts describe as extortion of businesses and travelers that brings in millions of dollars a year.