A top human rights group has urged Pakistan's government to end what it calls the practice of “enforced disappearances.”

Amnesty International said the disappearances have increased “dramatically” since Pakistan joined the U.S.-led war on terror following the September 11, 2001 terrorist attacks on the United States.

The London-based group said Pakistani government forces have detained hundreds, if not thousands, of residents of Pakistan's Federally Administered Tribal Areas on suspicion of cooperating with the Pakistani Taliban. It said some 2,500 people were reportedly in detention in the first half of 2010.

Amnesty said it and other human rights groups believe the number of people subjected to enforced disappearances could be much higher.

The group said the disappearances have occurred especially in the southwestern province of Baluchistan, the site of violence involving ethnic and religious armed groups and state security forces. The group said there were 93 recorded cases of people killed after being reported missing in Baluchistan from October 2010 to May 2011.

Amnesty said the primary targets are activists, journalists and students, noting that an increasing number have been found dead with their bodies showing signs of torture.

The rights group called on Pakistani Prime Minister Yusuf Raza Gilani to address the situation.

Pakistan has in the past rejected accusations of human rights abuses.