A 24-year-old woman was shot dead allegedly by a man in front of her brother and mother inside her house in the southeast Delhi's Jaitpur area, police said on Saturday.
The assailant on Friday night pumped four bullets into the woman, Pooja Yadav, killing her on the spot, police said.
The attacker, identified as Rocky from Haryana's Faridabad, has been arrested, they said.
According to police, Rocky disapproved of Yadav's 'illicit' relationship with his elder brother, Krishna Pradhan, a real estate dealer, and decided to kill her.
"Rocky told us that his elder brother was already married with four children. Because of his relationship with Yadav, his sister-in-law and mother would often fight with Pradhan. This led him to kill Yadav," said a police officer.
Yadav worked at Pradhan's office in Basantpur Village of Faridabad and lived with her parents and younger brother in Jaitpur Extention's Ekta Vihar locality.
She had done a beauty parlour course and had left her job at Pradhan's office seven months ago due to objections to her relationship with him by his family members.
"She was playing with kids outside her house before she was attacked by a person who came on a motorcycle. I was in the house with my mother. As soon as Pooja entered the house, the man opened fire at her," Yadav's brother Manoj said.
The 22-year-old said that he chased the attacker, but he pointed his gun at him and threatened to kill him as well.
The attacker fled on foot, leaving behind his motorcycle, which was without a number plate, police said.
Police through the engine number traced the ownership of the bike to one Narender, who revealed he had given it to Rocky on Friday.
When police raided Rocky's house in Faridabad, they didn't find him there, however, they tracked his location and nabbed him from the same area.
Yadav was unmarried. Her father works as a driver in private company and her younger brother is a private firm employee in Noida.
Police are probing whether Pradhan's other family members had a role in the killing.
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