Deadly U.S. drone strikes have targeted the mountainous area on Pakistan's border with Afghanistan, an area where militants from the shadowy Haqqani network have been staging attacks on U.S. forces at an alarming rate.
"It is from there that a militant leader named Haqqani has been sending his fighters to carry attack on U.S. forces...at an alarming rate," said Maj. Gen. John Campbell, commander of the 101st Airborne Division. Campbell is in charge of the region known as the federally administered tribal areas.
"We've had some tough times along the Pakistan border and dealing with the border, and the Haqqani network that comes across it. We've had several large spectacular attacks the over the last couple of months. All of them we have defeated back for the most part," said Campbell.
But the U.S. is hitting back hard. In January, there were 12 drone strikes, and in August, four. Now, drone strikes have spiked to at least 20 in September so far.
ABC News has counted at least 70 U.S. drone strikes in North and South Waziristan so far this year, counting multiple strikes on a single target as one strike. Targets consist of compounds and vehicles.
Officials tell ABC News that a threefold increase in special operations raids, resulting in a "treasure trove" of intelligence, has helped make the drone strikes possible.
The commander of U.S. and coalition forces in Afghanistan recently said there has been remarkably strong evidence leading to Pakistan's tribal areas.
"It links those who are in charge of the Haqqani organization with direct control -- minute by minute, in some cases of attacks," Gen. David Petraeus, International Security Assistance Force Commander, told ABC News in an exclusive interview earlier this month.
"There's a limit to the progress you can make here in Afghanistan if there is not also additional pressure put on the extremists who are in sanctuaries outside the country of Afghanistan," Petraeus said.
Petraeus is making the Haqqani network a major priority, and the strikes are a clear sign that the U.S. is taking matters into its own hands as frustration mounts with the Pakistani efforts against the militants.
U.S. Steps up Drone Strikes in Afghanistan
"The sanctuaries and safe havens, again, there will have to be more done about them," Petraeus said. "So there will have to be more pressure on them. There's no question."
ABC News' Richard Coolidge and Nicholas Schifrin contributed to this report.