ROUGH CUT (NO REPORTER NARRATION)

Three members of Afghanistan's national security force were killed on Thursday when a motorcycle loaded with explosives blew up in the eastern city of Khost, authorities said.

The provincial governor's spokesman, Baryalai Rawan, said the incident took place in Khost city on Thursday afternoon after a vehicle of the Afghan NDS operatives struck with a roadside bomb.

He added that three NDS operatives were killed and two others were injured following the explosion.

Another security official speaking on the condition of anonymity said that the NDS operatives were killed after a motorcycle packed with explosives went off near the vehicle of the intelligence operatives in Khost.

The the impact of blast shattered windows in nearby buildings and damaged several cars.

An eyewitness said the blast took people by surprise.

"I was taking away goods from my shop and suddenly an explosion happened. Some people said it was a