Balbir Gautam (55) had placed his quilt on the terrace to warm it which was opposed by his neighbour Manoj Gupta.
They had an heated altercation over the matter after which Gupta brought out a country made pistol from his house and fired at Gautam.
Gautam's wife threw a brick at Gupta, who also shot her dead.
Both the husband and wife died on the spot.
On receiving information police arrested Gupta.
Gautam's elder son had lodged an FIR against Gupta alleging that he killed both his parents.