Moments before his murder inside his home, 68-year-old D. K. Joshi was not inside his residence at Vasant Kunj.The retired government teacher was outside his house (probably strolling).He returned on seeing a ‘girl’ at the door pressing the calling bell.But as he came face to face with the person at the door, he soon realised it wasn’t a girl looking for him but a 17-year-old boy who lived in the building as a tenant till March this year. The boy was wearing a woman’s wig.The unusual sight didn’t probably bother him: why would his former tenant return after so many months sporting a woman’s wig? Joshi opened the door. An argument ensued as both of them stepped inside. The next moment, the boy stabbed him with a dagger. The Delhi Police on Tuesday arrested the 17- year- old for the murder.Joshi was killed on December 17 but the incident came to light on December 19. The police said the accused killed him in revenge. The deceased had earlier caught him stealing items from his house.Five police teams were hunting for the accused who was arrested within 48 hours of the incident.Police sources said an anonymous letter was found near the house of the victim naming the culprit. This helped the police zero in on the accused.The police found that two youth used to live as tenants in his apartment and had stolen money and jewellery from his house earlier this year. The accused and another boy lived with the old man from November 2009 to March this year.advertisementThe suspicion on the tenants proved right. ” After winning the trust of the old man, the accused had stolen cash and other valuable items along with the other boy. Joshi settled the matter out of court and the boy’s family paid him ` 3 lakh as compensation. But the boy remained remorseless and thought of eliminating the old man to settle the score,” deputy commissioner of police ( south) HGS Dhaliwal said.Joshi was seeking Rs 50,000 more from the family.The accused, preparing for the IIT entrance exam, was apprehended from the residence of his maternal uncle at E block in Gurgaon’s Sun City. He is from a well- off business family based in Singroli, Madhya Pradesh.For carrying out the murder, the accused arrived in the city on December 16 and stayed at his girlfriend’s place. She works in a beauty parlour in Kalkaji, the police said. He came with a dagger bought from Nepal in 2008.On the day of the murder, he borrowed a woman’s wig from the beauty parlour of his girlfriend and reached the old man’s residence along with a friend on a bike. He told his friend accompanying him that he had to meet someone who owes him money.” They parked the bike at some distance from Joshi’s residence.The accused asked his friend to wait for him. He then walked to the victim’s house wearing the female wig to avoid recognition,” Dhaliwal said.After killing the old man, the accused stole a laptop, a mobile phone and three wine bottles and fled from the backside. He stayed at his girlfriend’s place that night.From there he went to his uncle’s residence in Gurgaon.Surprisingly, the beat constable supposed to take the attendance of senior citizens every day did not know about the murder for two days. “The victim never wanted to get registered as a senior citizen as he was planning to relocate to America where his son worked.But our constable was still in touch with him,” Dhaliwal said.