MIR ALI, Pakistan (AP) — A suspected U.S. drone fired three missiles at a house in northwestern Pakistan, killing five alleged militants in the 14th such attack this month — the most intense barrage since the airstrikes began in 2004.

The house belonged to a local militant and was located in Datta Khel, a town in the North Waziristan tribal area that is controlled by insurgents who regularly launch cross-border attacks against NATO troops in Afghanistan, said intelligence officials on condition of anonymity Sunday because they were not authorized to speak with the media.

The exact identities of the dead militants were not known. U.S. and Pakistani intelligence officials have said most of this month's strikes have targeted forces led by Jalaluddin Haqqani, a commander who was once supported by Pakistan and the U.S. during the war against the Soviets in Afghanistan.

Haqqani has since turned against the U.S., and American military officials have said his network presents the greatest threat to foreign forces in Afghanistan.

The U.S. has pressured Pakistan to launch a military offensive against the organization, but Pakistani officials have pushed back — a move many analysts believe is driven by their desire to maintain a historical relationship with the group, which could be an ally in Afghanistan after foreign forces withdraw.

Without a Pakistani offensive, the U.S. has had to rely on CIA-operated drone strikes to target the network, which is based in North Waziristan and adjacent areas in Afghanistan.

Including Sunday's attack, fourteen missile strikes have killed more than 65 people since Sept. 2, according to an Associated Press tally based on Pakistani intelligence officials' reports. Many have struck in and around Datta Khel, which has a population of about 40,000 people and sits on a strategically vital road to the Afghan border.

U.S. officials do not publicly acknowledge the missile strikes but have said privately they have killed several senior Taliban and al-Qaida militants and scores of foot soldiers in the region that is largely out of the control of the Pakistani state.

Pakistani officials often criticize the strikes as a violation of the country's sovereignty, but the government is widely believed to help the U.S. carry out the attacks and criticism has been more muted in recent months.

U.S. forces began targeting Pakistan's tribal regions with aerial drones in 2004, but the number of strikes soared in 2008 and has been steadily climbing since then, with nearly 70 attacks this year, according to an AP tally.

Until now, the highest number of airstrikes inside Pakistan in a single month had been the 11 launched in January 2010 after a suicide bomber killed a Jordanian intelligence officer and seven CIA employees at a base in Afghanistan.