A 23-year-old woman was allegedly killed with an iron rod by a man in south Delhi's Malviya Nagar area on Friday for turning down his marriage proposal, police said.
The victim and the accused were first cousins, with their mothers as sisters, they said.
The accused had allegedly been following the victim for the last three to four days for a chance to talk to her, police said.
The victim, identified as Nargis, was attacked by 28-year-old Irfan when she was with him at a park near Delhi University's Sri Aurobindo College, police officials said, adding that the accused has been arrested.
Delhi Chief Minister Arvind Kejriwal slammed the state of law and order in the city following the incident and urged the Union home minister and the lieutenant governor to take strict measures.
'Another daughter was brutally murdered in Delhi, it is very sad. Law and order has become a serious issue in Delhi. It is a request to the LG and the Home Minister, make the police a little active. The safety of the daughters of Delhi and the people of Delhi is very important,' he tweeted.
Police said they got the information at 12.08 pm that a man hit a woman in her head at the Vijay Mandal Park in Shivalik A Block of Malviya Nagar and fled.
The woman's body was found under a bench with an injury to the head and an iron rod lying was found nearby, Deputy Commissioner of Police (south) Chandan Chowdhary said.
According to police, Nargis and Irfan were in a relationship earlier and there were also talks about their marriage, but Nargis's family finally disapproved of it.
Subsequently, Nargis had stopped speaking to Irfan, which made him even more agitated, police added.
Nargis completed her graduation this year and used to attend coaching classes in Malviya Nagar, they said.
Sources said the murder was preplanned and the accused claimed that he took the weapon from his house.
"The accused has claimed that he took the iron rod, which was used in the crime, from his house. He further claimed that he tried to approach the woman on Monday also, but could not meet her that day due to some reasons. We are verifying his claims," a source said.
The family members of the victim told police that after the marriage proposal was turned down, the families were not on talking terms.
She completed her graduation from Kamla Nehru College and was taking stenographer coaching, the sources said, adding that the accused did not have any permanent job and was working as a food delivery agent.
The Delhi Commission for Women has issued a notice to the police, seeking details of the murder.
The notice issued by DCW chairperson Swati Maliwal sought details on the FIR registered and the accused and any other action taken from the deputy commissioner of police (South) by July 31.
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