Four Afghan policemen were killed and five others were injured as militants carried out an attack on a security checkpoint in the Nachin area of the country's central province of Oruzgan, a security source stated on Sunday.

"Four policemen, including the commander of a security checkpoint, were killed and five others were injured in the attack", the source said, noting that the incident took place on Saturday night.

The source added that two police cars had been destroyed in the attack.

"Last night, the air force launched an airstrike on insurgents in the area and eight insurgents were killed," another source revealed on the condition of anonymity.

Earlier this month, five police officers and servicemen were killed in the Imam Saheb district of the Afghan northeastern Kunduz province in an attack by militants.