The collision took place between a JSK bus and an Orbit bus, they said. Orbit buses is co-owned by Punjab's Deputy Chief Minister Sukhbir Singh Badal.
The deceased have been identified as Pal Singh from Dharamkot, Vinod Kumar from Jalandhar and Gurbhej Singh from Shahkot while the identity of the woman is yet to be ascertained, police said.
"Those injured have been admitted to a hospital," SP Harmon Singh said.
Police were yet to ascertain the cause of the accident.
The orbit bus was going from Jalandhar to Muktsar while the GSK bus was going from Moga to Pathankot.