Two days after a pregnant housewife and her lover were strangled to death in a village near Karnal allegedly by her relatives, police have arrested four persons including the girl's father in connection with the 'honour killing'.Om Prakash of Ballah village, the father of 23-year-old Sunita, two relatives Rajesh and Ram Mehar, and one Dharamveer were arrested on Saturday night and produced before a duty magistrate on Sunday, police said.The court in Assandh town of the district has remanded the four, who are among 30 accused, to 14 days in judicial custody.Police said Dharamveer is the driver of one of the vehicles in which Sunita and her paramour Jasbir were bundled into after a mob pulled them out of a house in Phurlak village on Thursday night. The vehicle has been impounded.They said Om Prakash, the main accused, and the others have been charged under Sections 452 (house trespass with intent to assault and wrongful restraint), 364 (kidnapping), 302 (murder), 201 (causing disappearance of evidence), 316 (causing death of unborn child amounting to culpable homicide) and 120 B (criminal conspiracy).The lovers, both of the Jat community, were murdered after some 30 people attacked the house of Jasbir's sister in Phurlak village.Their bodies were displayed outside the family house in Balla village, apparently as a warning to others who might try to emulate the ‘immoral act’.Sunita, a divorcee, had eloped with Jasbir and was 6 months pregnant at the time of death.