Two car-bomb attacks by al-Shabaab militants killed at least 15 people and flattened homes in the central Somali region of Hiran on Wednesday, Reuters reported, citing a source involved in the rescue effort.

It was the latest in a series of attacks carried out by al-Qaida's al-Shabaab affiliate since government forces and allied clan militias began pushing insurgents out of territories they have long held since last year.

Al-Shabaab claimed responsibility for the bombings, saying the target of the attacks were renegade militiamen and soldiers. The group also claimed the death toll was 87.

Al-Shabaab has been fighting an insurgency against the Somali government since 2007. It was driven out of Hiran last year by government troops and allied clan militias known as the Makawisli, but continues to launch attacks.

The soldiers and militias were supported by U.S. and African Union troops during their offensive.

President Hassan Sheikh Mohamud's government claims that operations have killed hundreds of al-Shabaab fighters and recaptured dozens of settlements, although many of the claims of fighting cannot be confirmed by independent experts.

Al-Shabaab's actions have also limited international aid supplies, exacerbating the effects of the worst drought in the Horn of Africa in four decades.