Police said Mohammad Shams, a resident of Dhoke Bhattian in Gujar Khan, had gone to the house of his in-laws in the village to bring back his estranged wife, Tasleem Bibi.
However, when the woman refused to go with him, Shams shot her dead along with his father-in-law, mother-in-law and sister-in-law.
The victims were identified as Fazlur Rehman, 55, Khatoon Bibi, 45, Tasleem Bibi, 23, and Tayyaba Bibi, 20.
Shams also abducted the one-and-a-half-year-old son of Tayyaba Bibi, mistaking him for his own six-month-old son.
Rescue 1122 shifted the injured to the tehsil headquarters hospital Gujar Khan, where they were pronounced dead.
An official at the Mandra police station told Dawn that Tayyaba’s son had been recovered from the accused’s residence in Dhoke Bhattian. However, the killer was still at large and police were trying to arrest him.