Suspected American spies are being killed routinely in Pakistan's northwestern tribal region bordering Afghanistan, apparently to avenge US drone attacks.
Tribesmen in the region have said corpses appear in fields and on roadsides almost every day with written warnings pinned to their clothes: "All American spies will meet the same fate."
"Espionage has long been viewed as an egregious offence in the lawless borderland but residents say the current pace of assassinations is unprecedented," The Washington Post reported Friday.
The killings parallel a massive surge in CIA drone attacks on North Waziristan, home to a nest of insurgents that includes Al Qaeda and the militant Haqqani network.
CIA drones have fired 112 missiles on Pakistan's tribal areas this year, 88 percent of which hit North Waziristan, the daily said.
But tribesmen have now said the US campaign has had "far-reaching consequences" for people in North Waziristan and has provoked "cycles of violence" that are difficult to predict and impossible to control.
Several Pakistani officials, tribesmen and militants have said the strikes have forced residents to stay indoors and deny friends shelter, fearing allegations of spying.
"With scant proof, militants are purging suspected moles, and their willingness to do so has made the accusation a valuable tool for people seeking revenge for land disputes or other personal enmities," it said.
"They are just spreading terror by killing anyone," said Lt. Gen. Asif Yasin Malik, who commands all Pakistani troops in the northwest.
Pakistani security officials said the drone strikes were increasingly efficient in hitting militant targets although one intelligence official termed the CIA as "trigger-happy".
The intelligence official said 70 informants for the Inter-Services Intelligence (ISI) agency, which provides intelligence to the CIA for drone strikes, have been assassinated in North Waziristan since 2004, making the area nearly a "black hole" for spies.
The Post quoted North Waziristan tribesmen as saying that at least 30 corpses have turned up during the past three months.
Pakistani officials said the assassinations could be viewed as a sign that the Taliban feel threatened by drones.
North Waziristan residents said the dread of being labelled a traitor exceeds that of being struck by a drone.