The assaults — at least three in Kabul, two in Nangarhar Province and one each in Paktia and Logar Provinces — began simultaneously at 1:45 p.m., and witnesses described nearly identical patterns of attack: light gunfire, followed by explosions and then protracted firefights with Afghan security forces, with the militants in several cases fighting from empty buildings or construction sites near their main targets.

Western officials said the attacks bore the hallmarks of the offshoot Haqqani network of the Taliban, which has focused on attacks against high-profile Afghan government and foreign targets. The network is based in Pakistan, a source of tension between the Pakistani government and the United States. The Haqqanis have become one focus of American military efforts, and the attacks on Sunday raised troubling questions about the state of intelligence on the supposedly weakened militants’ movements.

The Haqqani network was directly involved in one of the last major attacks in Kabul, an assault on the American Embassy in September, and that, too, involved militants raining down rocket and gunfire from an unfinished building nearby, suggesting a lasting security weakness within even the most secure districts of the capital.

“This does have all the hallmarks of Haqqani on it,” said Col. Daniel J. W. King, spokesman for NATO. “It’s been over 150 days since the Haqqanis launched a successful attack on Kabul, they have to do this if they are going to have any credibility.” He added, “If this is the best they can do to start their fighting season, then obviously the Afghan security forces and others are having a significant impact.”