MOGADISHU, Somalia (AP) — An explosives-laden vehicle detonated Saturday at a security checkpoint in the central Somalia city of Beledweyne, killing at least 18 people and wounding 40 others, authorities said.

Abdirahman Dahir Gure, the interior minister of Hirshabelle state, announced the toll to journalists.

“Twenty of the wounded have been admitted to Beledweyne hospitals, while another 20 are in critical condition, prompting a request for their airlift to Mogadishu for advanced medical treatment,” he said.

Hirshabelle is a state that includes Beledweyne, which is the capital of the Hiran region and has been the center of the Somali government’s latest military offensive against extremists from East Africa’s al-Qaeda affiliate, al-Shabab.

Images on social media showed black smoke billowing and a smashed truck cab blazing at the checkpoint.

Dr. Suleyman Abdi Ali, the director of Beledweyne General Hospital, said the bodies of 10 victims were brought to his hospital.

There was no immediate claim of responsibility from al-Shabab, which often carries out such attacks and controls parts of Somalia.

“It was a truck loaded with explosive devices that forcefully passed through the government-manned checkpoint, and a pickup vehicle belonging to security personnel was chasing it when it exploded,” witness Abdikadir Arba, who said he was about 200 meters away and was one of the first responders, told The Associated Press by phone.