The Delhi Police on Tuesday formed a special investigation team (SIT) to probe into serial rape and murder of as many as 30 young children, as confessed by the accused himself.

According to reports, in addition to Delhi, the SIT will track similar cases allegedly involving Ravinder Kumar in neighbouring districts of Haryana and Uttar Pradesh also.

"After his shocking revelations, we have formed an SIT to probe the case further... The team along with local police will also investigate cases in Haryana and Uttar Pradesh," IANS quoted deputy commissioner of police (DCP) Vikramjit Singh.

The 24-year-old Kumar, a native of Badaun district in UP, reportedly told police that he has been targeting young girls in Delhi, UP and the National Capital Region (NCR) since 2008.

Kumar was arrested last week in connection with the rape and murder of a six-year-old girl, who went missing on 14 July from outer Delhi's Begumpur area.

In course of investigation, the number of cases rose dramatically from 15 to 30. The man's revelations have shocked the police, as most of his victims were under the age of 14. They now suspect that the number of rape and murder of children might even reach 40.

"I am deeply shaken from inside... I cannot express in words what all I am going through," Singh told IANS.

The DCP said that Kumar was on Monday taken to areas like Narela, Bawana and Alipur in outer Delhi as he had named these as places of occurrence in course of interrogation. Apart from these three areas, police were now also looking into cases of missing children filed in last five years in Vijay Nagar, Begumpur, Kanjhawala, Samaypur Badli and other areas.

According to police, Kumar would lure children with candies and kill them if they resisted. He would even have sex with their bodies. He usually committed the crimes in the afternoon or early morning.

A young girl, whose father happened to be a labourer at a Delhi Metro Rail construction site, was his first victim when he was just 17. However, no case was filed so there could be no action against the teen and later he went on to sexually assault and kill many more children.

Kumar was accused of kidnapping, sodomising and strangling another labourer's son in 2009 in Vijay Vihar area of Delhi. However, nothing happened to him for the lack of evidence. IANS reported quoting police that he had killed 11 of his victims after they resisted his attempts to sexually assault them or threatened to expose him.