Al-Qaeda’s operations chief in Pakistan has been killed, according to U.S. officials, marking the latest in a series of losses for the terrorist network.

One official said Abu Hafs al-Shahri, a Saudi, was killed in Pakistan’s tribal areas earlier this week, less than a month after the killing of al-Qaeda’s no. 2 official. It was unclear how he was killed, but the CIA has been using armed drones to target militants in the region.

Shahri’s death “removes a key threat inside Pakistan,” the official said, speaking on condition of anonymity. The official said Shahri had collaborated closely with the Pakistani Taliban to coordinate attacks with al-Qaeda.

Pressure on al-Qaeda — driven mainly by the CIA’s drone campaign — has wiped out a handful of the terrorist network’s top leaders over the past several months, forcing the group to promote members who were relatively unknown into positions of leadership.

Shahri was far less notorious than al-Qaeda’s no. 2 official, Atiyah Abd al-Rahman, but was seen as a “contender to assume some of Atiyah’s duties,” according to a second U.S. official.

The rise of Shahri, who was little-known, illustrates the rate of promotion within al-Qeada as the CIA’s drone campaign continues to pick off senior leaders.
     “They are not having the period of apprenticeship they had in the past, which may be one reason why they are getting nailed faster,” said Bruce Hoffman, a counter-terrorism expert at Georgetown University.  “The people still out there have to be convinced their time is near and are spending more time thinking about that than planning operations; it realigns their priorities from attacks to survival.”

U.S. officials have said that al-Qaeda’s core now poses less of a threat to the United States than some of its affiliates and associated movements, primarily in Yemen, Somalia and North Africa.

Earlier this week, the Defense Department’s undersecretary of defense for intelligence said that al-Qaeda’s core group in Pakistan could be rendered incapable of carrying out attacks “within 18 to 24 months.”

A Pakistani intelligence official based in North Waziristan said he suspected, but could not confirm, that Shahri was killed in a drone strike on Sept. 11. In that strike, the official said, two drone-fired missiles hit a motorbike and a nearby house, killing two people immediately and injuring two others who died later. Locals said among the dead was an Arab, but the official said al-Qaeda-affiliated militants quickly blocked the area and removed the bodies, so it was impossible to confirm the identities of those killed.

Correspondent Karin Brulliard in Islamabad and special correspondent Haq Nawaz Khan in Peshawar contributed to this report.