TWITTERSecurity forces are on the scene
The attackers broke into a building in the Afghan capital following an explosion, according to a security official.
One of them was subsequently killed by guards while another used hand grenades to fend off security forces.
The station's official Twitter account said staff members reported several casualties, and staffers reached by phone said between two and five people had been killed in the attack.
Kabul police spokesman Basir Mujahid said casualties were feared but the number was still unclear.
More than 100 employees are still believed to be inside the