When the United States pulled out its forces from Afghanistan in 2021, it left behind around $7 billion worth of military equipment and weapons, including firearms, communications gear, and even armored vehicles, reports Radio Free Europe/Radio Liberty.

The Taliban got a huge cache of arms after the US-backed Afghanistan government collapsed in 2021.

Since the Taliban takeover, some of the American military gear and weapons have turned up in neighboring Pakistan, where they have been used by armed groups, according to experts and security officials, reports the website.

Observers say the influx of U.S. weapons has boosted the military capabilities of the Tehrik-e Taliban Pakistan (TTP) militant group and ethnic Baluch separatist groups that are waging insurgencies against the government in Pakistan, which has witnessed a surge in violence over the past two years.

"These weapons have added to the lethality of such groups," Asfandyar Mir, a senior analyst at the United States Institute of Peace, told Radio Free Europe/Radio Liberty, adding that a "robust and in many ways growing black market" for U.S. weapons is thriving in Pakistan.

Experts say armed groups have obtained advanced U.S. weapons and equipment like M16 machine guns and M4 assault rifles, night-vision goggles, and military communication gear.

Abdul Sayed, a Sweden-based researcher who tracks the TTP, said the group's access to sophisticated combat weapons has had a "terrifying" impact, especially on the lesser-equipped police force, in Pakistan.

A police officer in the northwestern province of Khyber Pakhtunkhwa, which has borne the brunt of the TTP attacks, told RFE/RL that they were sitting ducks for militants.

"The fact is that they can see us in the dark while we can't. That gives the terrorists an enormous advantage," said the officer, who spoke on condition of anonymity because he was not authorized to speak to the media.