One soldier and 16 militants were killed on Saturday when the Taliban insurgents launched a major attack from Afghanistan side, triggering hours-long gunbattle at Pakistan border post in restive northwestern tribal area, security sources said.

A security official said around 200 militants gathered at the village Ghund in Kunar province of Afghanistan and launched the attack at 5:15 am (local time) at Nao Top check post in Bajaur tribal district.

The army responded to the attack, resulting in the fierce gunbattle which continued for several hours, the sources said.

The army said 16 militants were killed while one soldier embraced martyrdom and two others were critically injured.

“Attack was effectively repulsed after the fierce fighting,” the official said.

The injured are being evacuated. Helicopter gunships have been sent as reinforcement, which engaged the militants.

Some helicopters have strayed into Afghan territory, according to some media reports.

Nobody claimed responsibility for the attack but military said the attackers were from Bajaur and Swat areas.

They are loyal to Taliban top leader Maulana Fazlullah who is hiding in Kunar since 2009 after escaping a military action in Swat.