A radio station run by the Islamic State (Isis) in Afghanistan has been destroyed in air strikes, which also killed several militants. The radio station, known as "Voice of the Caliphate", has been a main propaganda vehicle for the Islamist group in the eastern Afghan province of Nangarhar.

Both Afghan and American authorities have confirmed the hit but details are still sketchy on who conducted the air strikes. Local reports suggest at least 29 militants including the key insurgents behind the radio station were killed in the attack.

A spokesman of the provincial government, Hazrat Husain Mashriqiwal, said a self-styled court run by the IS was also brought down by the strikes. A statement from the local government read: "The foreign forces conducted four air raids against IS positions in Momand Dara locality of Achin district Monday night, killing 29 IS militants and destroying an IS radio station."

Following the Afghan version, an official statement from the US Army's Colonel Mike Lawhorn said: "US forces conducted two counter-terrorism airstrikes in Achin district," without offering more details.

The IS radio station was launched in December 2015 as a key recruitment tool and to broadcast propaganda materials by the IS. The launch of the facility had rattled Afghan authorities already struggling to combat the Taliban's insurgency.

The attack was not the first attempt by Afghan forces to uproot the radio station. At least two previous bids had gone in vain as the station pressed ahead with its broadcasts. Local officials had also suspected the IS extremists managed to broadcast the messages through a mobile studio, making it difficult to pinpoint the exact location.

There are growing concerns that the IS is increasing its foothold in volatile Afghanistan both by snatching operatives of the Afghan Taliban and by drafting fresh militants. Pentagon has also issued a warning saying the Afghan arm of the Iraqi extremist group has become "more operationally active", aimed at carving out a territory for itself.

The emergence of IS also poses a huge challenge to the Kabul government, which has battled terror on its soil since the turn of the century. It has also increased rivalry between the Taliban and IS, which has intensified in recent months as the latter makes serious inroads.