PESHAWAR: Dozens of armed militants raided a paramilitary checkpoint in northwest Pakistan on Wednesday, sparking clashes that left three soldiers and at least 10 attackers dead, officials said.

The area on the Afghan border, branded by Washington the most dangerous place on Earth and the global headquarters of al Qaeda, is cut off to journalists and aid workers and it was not possible to confirm the death toll.

“More than 30 militants attacked a Frontier Corps checkpost in Dabori area of Orakzai tribal region on Wednesday afternoon and killed three security persons,” a security official told AFP in Peshawar.

“The security forces responded to the attack with full force and used helicopters for shelling on the militants. At least 10 militants were killed in the response.”Seven troops were injured during the firefight.

Orakzai is one of seven districts in Pakistan's semi-autonomous tribal belt, where Taliban and al Qaeda-linked militants have carved out strongholds used to plot attacks on Pakistani, Afghan and Western targets.