Sitapur, June 22 : An investigation into a case of a missing bike, led the police in Uttar Pradesh's Sitapur district to a couple who had killed their 18-year-old daughter over her relationship with a youth. The naked body of an unidentified girl with her throat-slit, was found near a pond in Saholi village under Sandana police station limits last week. Cops failed to ascertain the victim's identity for nearly three days, but a complaint about a missing motorcycle by one Ram Avtar of nearby Pakarnarayanpur village, gave them a breakthrough in the murder case. ASP (Sitapur) N.P. Singh said the police got suspicious after receiving information that one Pankaj Kumar, along with his wife, daughter and two sons, was missing for four days after borrowing a motorcycle from Ram Avtar. He said the complainant Ram Avtar informed that Pankaj Kumar, a native of the same village, had borrowed the bike to visit his in-laws' place on June 16 and had been missing since then. Probe confirmed the identity of the deceased girl as Pankaj's daughter, following which the police reached his in-laws' house in Begurawa village nearby and took Pankaj and his wife into custody, after which the couple confessed to killing their daughter. "The couple confessed that they were fed up with their daughter, who had a relationship with a youth belonging to a different caste. The family lived in Delhi where they worked as domestic help. The couple visited their native village in Sitapur a week ago with a plan to eliminate their daughter, if she did not agree to end this relationship," the official said. "As per plan, Pankaj left his village telling people that he was going to visit his in-laws' house on June 16. He strangulated his daughter with the help of his wife after halting at a deserted place near Saholi village. The couple also slit the throat of the girl and fled after disposing of the body there itself. The couple's two minor sons were also present when the crime was executed," said O.P. Tiwari, in-charge of Sadana police station. He said the accused removed the girl's clothes so that her identity could not be ascertained. He said the axe and the scarf used in the killing were also recovered from the accused and they have been booked under Indian Penal Code sections 302 for murder, 120-B for criminal conspiracy and 201 for concealing the body. /IANS