Two missiles fired from a drone struck a vehicle in which the four people were riding, CNN reported, quoting the officials.
A second suspected drone strike targeted a house in the same area as the first attack near the town of Miranshah but no one died in that incident, the report said.
There were two similar suspected drone strikes earlier this month but they were neither confirmed nor denied by the United States. Prior to the those strikes, there had been a lull in the program following a Nov. 26 NATO airstrike in the tribal regions in which 24 people were inadvertently killed.
The victims in the Monday strike were believed to be from Turkmenistan, the BBC reported, quoting local administration officials.
U.S. officials have said they believe the North and South Waziristan regions provide havens for al-Qaida and Taliban militants, who use them to launch attacks on U.S. and NATO forces in Afghanistan.
Last week, CNN reported a senior al-Qaida operations planner, Aslam Awan, was among those killed in a Jan. 10 drone strike on a compound near Miranshah.
He was described as a key member of the organization and had been tracked by the intelligence community. At the time of his death, Awan was reported to have been planning attacks against the West.