Somali towns have been witnessing sporadic attacks linked to the al-Shabaab group / Photo: Reuters

At least six people were killed in an explosion targeting a passenger bus travelling in a region outside Somalia's capital on Wednesday, the state news agency said.

Somali News Agency, citing the Mohamed Ibrahim, the governor of Lower Shabelle region, said the attack happened on a road between Qoryoley and Marka districts and another 12 people had been injured.

The news agency said on its account on X, formerly known as Twitter, that Ibrahim had said a terrorist attack had caused the explosion.

Ibrahim did not say which group was suspected to have carried out the attack. Al Qaeda-linked al Shabaab has in the past taken responsibility for similar attacks.

The group has been fighting since 2006 to topple Somalia's central government and establish its own rule based on a strict interpretation of Islamic Sharia law.