The United States has deployed hundreds of troops along Afghanistan's border with Pakistan's tribal region.

Reinforced with gunships and heavy weaponry, some 500 of the forces had been stationed near Afghanistan's border with Pakistan's North Waziristan region, a senior Pakistani government official told.

Tribal sources, said that a curfew had come into force, preventing the Pakistani troops' freedom of movement in the violence-hit region.

Last month, former US Joint Chief of Staff Admiral Mike Mullen claimed that Pakistan's intelligence agency was supporting the network, which has been blamed for assault on the US embassy in the Afghan capital, Kabul. "The Haqqani network, for one, acts as a veritable arm of Pakistan's Inter-Services Intelligence agency," he had asserted.

The remarks prompted harsh responses from Pakistani officials, with the country's Foreign Minister Hina Rabbani retorting that “this particular network, which the United States continues to talk about, is a network which was the blue-eyed boy of the [US Central Intelligence Agency] CIA itself for many years.”

"It is something that goes very, very unappreciated on our side,” she added, "This is unsubstantiated. No evidence has been shared with us."

Washington has frequently blamed Islamabad for not doing enough to fight terrorism in its troubled northwestern tribal belt, which runs along the Afghan border.