The police said the incident occurred on Wednesday night at around 11 pm when the deceased's father informed them about his daughter being missing.
According to the police, deceased Kajol, who was playing with her younger brother in a rented room in Ghazipur's Dairy Farm area, went missing.
"Her parents searched and enquired about her in the neighbouring houses, but later found her murdered with throat slit with some sharp-edged weapon on the terrace of the house. Six other tenants also live in the same building," a senior police officer said.
"The family members are suspecting that black magic could be the reason of this murder. Her body has been sent for postmortem examination to ascertain whether she was also sexually assaulted," he added.
"She was playing outside the room, while the other family members were watching television. Probably, the accused lured her, took her to the terrace and killed her. Police suspect the role of a tenant who is missing since the murder," Kajol's mother Munni Devi told IANS.
"We are enquiring with tenants and their neighbours to identify the accused. CCTV camera footage is also being examined," the officer said.