Police in India have charged two men and a policewoman in connection with the rape and murder of at least 19 women and children in a Delhi suburb
Businessman Moninder Singh Pandher has been charged with conspiracy while his servant Surinder Koli is charged with murder, rape and abduction.
The two were arrested after body parts were found near their house in Noida. A policewoman is charged with negligence.
Both men have had trouble finding lawyers, so high has been public anger.
The charges mark the start of formal legal proceedings in the case, which Indians have watched unfold with horror.
Addressing a press conference in Delhi, Central Bureau of Investigation (CBI) joint director Arun Kumar said Mr Pandher, who owns the so-called "house of horrors", was charged with conspiracy and destroying evidence.
The businessman has denied being responsible for killing children.
He was charged with "using his house as a brothel and using prostitutes for sexual purposes", but was apparently unaware of the murders, the CBI said.
His servant is charged with abducting, raping and murdering those whose bodies were found in a sewer near the house in Noida in December.
Mr Kumar said police believed Mr Koli was a psychopath.
He said the servant had admitted to eating the flesh of some of those who had been killed, and there was some suggestion he was a necrophiliac.
"This looks unnatural, but our investigations show Pandher was not aware of the murders," Mr Kumar told reporters.
"All over the world there is no example of two psychopaths living together or participating in the same crimes."
Policewoman Simranjit Kaur, whose arrest was announced on Wednesday, is charged with alleged negligence and dereliction of duty. She denies the charges.
She was the sub-inspector in charge of the police post in the Nithari area of Noida, where the murders took place.
The CBI took over the case amid mounting accusations that local police had done nothing about the murders.
Many locals say police failed to act because most those reported missing came from poor families.
Residents say as many as 40 children have disappeared in the area over the past two years.
The two main accused have been questioned by CBI officials and have also undertaken lie detector tests.
Earlier this month, Mr Koli made what the authorities say was a confession before a magistrate.
A video recording of his statement has been made which police say will be used in evidence in his trial.
Officials said that details of the confession will be revealed only when the trial is underway.
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