ISLAMABAD, Pakistan — An American drone attack killed 23 people in North Waziristan on Friday, Pakistani military officials said, in a strike against militants that appeared to signify unyielding pressure by the United States on Pakistan’s military amid increasing opposition to such strikes.

The strike came a day after the chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, met with the Pakistani military chief, Gen. Ashfaq Parvez Kayani, and asked that Pakistan do more to fight militants who use North Waziristan as a base from which to attack United States and NATO forces in Afghanistan.

The assault was the second show of the United States’ determination to continue drone attacks since the head of Pakistan’s spy agency, Lt. Gen. Ahmed Shuja Pasha, met this month in Washington with Director Leon E. Panetta of the Central Intelligence Agency to request a halt to the strikes.

Friday’s attack could further fuel anti-drone sentiment among the Pakistani public. A government official in North Waziristan told Pakistani reporters that five children and four women were among the 23 who were killed.