A suspected U.S. drone attack in Pakistan's volatile tribal area killed five people Tuesday, as part of an unprecedented wave of strikes since a deadly attack against the CIA across the border in Afghanistan, said intelligence officials.

The two missiles slammed into a compound and a nearby vehicle in the Deegan area of North Waziristan, a zone dominated by the Haqqani network, an Al Qaeda-linked Afghan Taliban faction that many suspect helped orchestrate the Dec. 30 suicide bombing that killed seven CIA employees at a remote base in Khost province.

Tuesday's strike was the 12th since the CIA attack, an average of one about every day and a half. The unmanned aircraft have also targeted the leader of the Pakistani Taliban, Hakimullah Mehsud, who appeared in a video alongside the Jordanian man who carried out the suicide bombing. But a series of strikes against his stronghold in South Waziristan apparently failed to take out the militant leader.

In Tuesday's strike, four people were killed in the compound and one in the vehicle, said the intelligence officials. The victims' identities were unknown, the officials said, speaking on condition of anonymity because they were not authorized to talk to the media.

The area hit in the attack is located 18 miles west of the town of Miran Shah and 12 miles south of the Afghan border. The area abuts Khost province, where the Haqqani network also holds dominance.

U.S. military commanders in Afghanistan believe the Haqqani network poses the most serious threat to coalition troops operating in the country. The Obama administration has pressed Pakistan to target the group and other militants staging cross-border attacks against U.S. and NATO troops.

But the Pakistani government has resisted, saying it has its hands full battling groups like the Pakistani Taliban that are waging war against the state. More than 600 people have been killed in Pakistan since the army launched a major ground offensive against the Pakistani Taliban in South Waziristan in mid-October.

Given the Pakistani government's reluctance, the U.S. has increasingly turned to drone strikes as a way to target militants in the country who pose a threat to its troops in Afghanistan. The U.S. does not usually comment on the strikes or their targets, but officials have said in the past that they have taken out several senior Al Qaeda and Taliban leaders.

While the Pakistani government publicly condemns the strikes as violations of its sovereignty, it is thought to have a secret deal with Washington allowing them.