A tailor in India has confessed to abducting, molesting and raping hundreds of schoolgirls over the last decade, said Delhi police, uncovering what may be one of the biggest serial paedophile cases in the country in recent times.

Sunil Rastogi, a 38-year-old married man with five children, was arrested on Saturday by police investigating the sexual assault of three girls aged nine and 10 in the east of the Indian capital.

“This criminal, Sunil Rastogi, is from Rudrapur in Uttar Pradesh, and is a tailor by profession,” Omvir Singh Bishoi, East Delhi’s deputy commissioner of police, told a news conference. “During interrogation he told us that at least once a week he would come from Rudrapur and, in order to satisfy his paedophile lust, he would target girls between the ages of seven and ten years old.”

Rastogi was charged with rape, aggravated penetrative sexual assault of a minor, and criminal intimidation, in the three cases, said police, and is also being investigated for related paedophile crimes.

Police said Rastogi could not remember the exact number of girls he had sexually assaulted since 2004, but said it could be “hundreds”.

Wearing a red, white and green striped sweater and a red balaclava covering his face, Rastogi was paraded in front of the media. “I used to take them (the girls) to a secluded area,” he said as he stood handcuffed to a policeman. “I don’t know why I did it. I liked it.”

Child sex abuse is widespread in India, but is largely considered taboo in its conservative society and ignored within families, say activists, who say victims are often afraid to come forward for fear of being blamed for the abuse.

There were more than 94,000 crimes committed against children in 2015, says the National Crime Records Bureau, with almost 40% of cases being sex offences such as rape, molestation and sexual harassment.

Police said they began investigating Rastogi in December after receiving a complaint of a 10-year-old girl who had escaped attempted rape in Delhi’s New Ashok Nagar area. Two similar complaints from other girls in the same area were received on 10 January, said police, and after scouring through hours of CCTV footage of the area, and using sketches and photographs to identify him, Rastogi was arrested.

He has been sent to judicial custody for two weeks, said police, and an investigation team will look into other sexual assault cases in Delhi, Uttarakhand and Uttar Pradesh.

Activists and politicians questioned how Rastogi managed to abuse so many girls and evade arrest for over 10 years, despite having served jail time for a previous sexual offence in 2006.

Swati Maliwal, Head of Delhi’s National Commission for Women, said the case was “horrifying”. “This serial rapist shud get death 4 raping 500 little girls over 13 years. His case shud be heard urgently in fast track mode,” tweeted Maliwal.