A serial rapist now in custody may have targeted more than 50 victims although he claims he didn't rape all, police said on Monday.

 While eight cases have been confirmed, the police fear many cases may have remained unreported.

"We are still investigating and are waiting for the victims' parents to come forward to file complaints," Deputy Commissioner of Police Omvir Singh Bishnoi told . 

"We were told by the accused, Sunil Rastogi, that he managed to rape only 20 per cent of the total number of victims he attacked. We suspect that he may have attempted to rape 50 minor girls or more," Bishnoi said.

The 38-year-old tailor hails from Uttar Pradesh and allegedly raped a minor girl and molested two others -- aged between nine and 10 years -- in New Ashok Nagar in east Delhi last week.

He was arrested on Saturday night.

Rastogi confessed to sexually molesting a number of minor girls in Ghaziabad in Uttar Pradesh and Rudrapur in Uttarakhand besides New Ashok Nagar in the national capital. 

Several cases of molestation, theft and drug abuse were registered against him in various police stations, the officer added.

According to the police, three cases of child rape and molestation under the Protection of Children from Sexual Offences Act (POCSO) were registered at the New Ashok Nagar police station on January 10 and 13.

Rastogi, a desperate paedophile, used to lure the minors claiming their father had sent him to give them clothes and articles. He would then take his victims to isolated corners where he tried to rape them.

He also targeted students from government girl schools. After raping them, he threatened them with dire consequences if they disclosed the assault to their parents, the police added.

After each attack, Rastogi would return to Uttar Pradesh to evade arrest.

A brain mapping and narco analysis test would be conducted after Rastogi's medical test, the officer said.