The bodies have been sent to Deen Dayal Upadhyay Hospital for the post mortem.
Two persons were found dead in an apartment building at west Delhi's Kirti Nagar area on Thursday afternoon, police said.
The police received information regarding the incident on the second floor of a building in Ramesh Nagar at 3.31 pm.
When they reached the spot, they found a man hanging from a ceiling fan while a woman was found dead on the bed, Deputy Commissioner of Police (West) Ghanshyam Bansal said.
The victims have been identified as Vijay Kumar (28) and Anchal (25). They were residents of Patel Nagar and Anand Parbat and had known each other for years, the police said.
Mr Kumar was a gym trainer and Ms Anchal was studying in Canada. Crime and forensic teams were called to the spot for inspection, Mr Bansal said.
Prima facie, a case of murder is being registered at Kirti Nagar police station. CCTV footage, call records details and autopsy reports will be analysed, he said.
There were no visible marks on the woman's body. The post mortem will ascertain the exact cause of death, the police said.
The bodies have been sent to Deen Dayal Upadhyay Hospital for the post mortem, which will be done on Friday.
Mr Kumar lived in the house alone and the woman came to Delhi in January. It is being verified whether they got married in court as their family members are not aware, the police added.
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