The armed group Al-Shabaab claimed responsibility for the car bomb attack on Saturday in the capital of Somalia, Mogadishu, in which 81 people died, while the national security agency said the attack "was planned by a foreign country ".
The attack hit a busy checkpoint in the southwest of the city, leaving charred and twisted vehicles at a crossroads in the deadliest assault in two years in the Horn of Africa.
Dozens more were injured in an area obstructed by traffic due to security control and a tax office that charged truck and bus fares.
"… the Mujahideen carried out an attack … aimed at a convoy of Turkish mercenaries and apostate militiamen escorting them," Al-Shabaab spokesman Sheikh Ali Mohamud Rage said in an audio message.
Among the dead were 16 students from the private university of Banadir, whose bus passed the crossroads when the bomb detonated.
Mogadishu is regularly beaten by attacks by Al-Shabaab, who has fought for more than a decade to overthrow the Somali government.
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But for the first time, Al-Shabaab apologized to the civilian victims of the attack, which he justified as necessary in the fight against the Somali state and its foreign sponsors.
"We are very sorry for the casualty inflicted on our Somali Muslim society, and we are extending our condolences to Muslims who lost their lives or (were) injured and / or destroyed their property."
Al-Shabaab does not usually claim attacks that cause such high rates of victims among the civilian population, for fear of losing the support they still enjoy with some Somalis.
The message also accused Turkey of trying to control Somalia's resources. Among the victims were Turkish citizens.
Turkey is a major donor and investor in Somalia, especially in humanitarian aid and reconstruction. Turkish companies manage the port and Mogadishu airport.
Meanwhile, Somalia's national security agency, Nisa, said the attack was planned outside the country.
Nisa wrote in a tweet that she had given the government a preliminary report on the attack. He did not mention the country and did not publish the report.
However, he added: "To complete the ongoing investigation, we will seek help from foreign intelligence agencies."
The death toll rose to 81 on Monday after two victims died from their injuries, the Somali information ministry said.
One of the new deaths was among the wounded who had been evacuated to Turkey through a Turkish military plane on Sunday.
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Saturday's attack was the largest in Somalia since a truck exploded in 2017 near a fuel tanker in Mogadishu, creating a fireball that killed more than 500 people.
In 2010, Al-Shabaab declared his loyalty to al-Qaeda. But their fighters fled the posts they once held in the capital, Mogadishu, and since then they have lost many fortresses.
They maintain control of large rural areas of the country and continue waging a guerrilla war against the authorities, managing to inflict bloody attacks at home and abroad.
The US military said Sunday that it had killed four "terrorists,quot; in three air strikes against Al-Shabaab.
The United States African Command (AFRICOM) said two fighters were killed and two vehicles were destroyed in Qunyo Barrow, while two other militants were killed in Caliyoow Barrow.
In an April statement, AFRICOM said it had killed more than 800 people in 110 attacks in Somalia since April 2017.