Somali officials say at least 20 people have been killed in a massive roadside explosion that engulfed a passenger bus on the main highway linking Mogadishu to Afgoye, 30 kilometers west of the capital.

A police officer at the scene, Abidkadir Mohamed, told the Reuters News Agency it was a remotely controlled bomb along the road that exploded.

Deputy Chairman of Afgoye, Abdullahi Hassan, who went to the scene, said the blast destroyed the minibus.

“We have a big tragedy here,” he told VOA. “Everyone is dead, you only see pieces of dead bodies, hands, legs.”

He said it’s believed 21-23 people were traveling on the bus.

“The blast hit the bus early Thursday morning,” Hassan said.

No one has claimed responsibility for the attack so far but al-Shabab often carries out deadly attacks on the Somali government and African Union peacekeepers. The group is also known for targeting civilians and hotels.