A police officer who declined to be named told Xinhua that a car filled with explosives went off as police were checking vehicles in Mogadishu's Bondhere District, causing deaths and injuries.
"The blast happened in a traffic area at a police checkpoint, so far we can confirm four people died in the explosion. We are establishing more details on the incident," the officer said.
Independent sources said among the dead included a Somali military officer and her bodyguards while a lawmaker was among those injured in the blast.
Abdulkadir Abdirahman Adan, director of Mogadishu's free ambulance service Aamin Ambulance, said that they had taken 12 injured people from the scene.
The blast came barely four days after a car laden with explosives went off at El-Gabta junction in Mogadishu's Hamarweyne District leaving no casualties.
Al-Qaida-allied group al-Shabab, which is fighting to overthrow the government, claimed responsibility of the latest attack.
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