Parents of a nine-year-old boy who was sexually abused by a convicted paedophile are demanding to know why authorities failed to prevent him attacking their son.

Michael Carroll, 57, is classed as a high risk sexual offender with a string of offences going back to 1987, including being jailed for a year in 1998 for depraved abuse of a six-year-old boy.

He was supposed to have received regular monitoring visits by the police’s Jigsaw (sexual offences) team after his release to see if he was conforming to the terms of his sexual offences prevention order (Sopo), including not having unsupervised contact with children.

But he was still able to freely worm his way into his unsuspecting victim’s family's life.

The victim’s father, who cannot be named for legal reasons, said: “Out of the 57 visits between 2009 and 2013 there were only 21 visits that were actual meetings and that works out as less than one every two months.

“We feel aggrieved that he was not monitored properly because it left him with a free rein to attack our child.

“If they had been stricter then maybe it would not have happened.

“The Jigsaw team has a lot of questions to answer.”

Handyman Carroll worked his way into the lives of the victim’s family after recruiting his victim’s older brother to help out with his work.

He said he liked to work with youths who were having behavioural problems at school because he said it helped them learn a trade and give them something to focus on.

The family gradually trusted him more and more and sent him birthday cards addressed to uncle and he babysat for the family and took the two older boys swimming.

During this swimming trip Carroll, from South Norwood, told them he could not dive with them because of his heart condition so sat on his own in the learners pool.

And on June 3 last year while babysitting, Carroll sexually abused the nine-year-old boy.

Before the boy undressed to take a shower at bedtime, Carroll sexually abused him.

And then when the child had come out of the shower and was dressed in a onesie, Carroll abused him again.

Your Local Guardian: The victim's parents want to know why paedophile Michael Carroll was free to attack their son

The boy's parents are demanding answers from the police

The boy’s mother said: “When my son told me what had happened I was just in shock and I instantly felt sick.

“Mike seemed such a nice bloke and you do not think that he was capable of doing that.”

But the day after they reported what had happened they received a call from the police stating Carroll was well-known to them.

The victim’s father said: “The man said lock all your windows and doors and do not let your children out of your sight. We will be there within the hour.

“The sound of his voice was haunting in how panicked he was and we were sitting here shaking wondering what Carroll had done before.”

The victim has been traumatised by what Carroll did to him and his parents are seeking counselling for him.

His father added: “For a nine-year-old to go through that before they have even thought about girls and they have been subjected to something that is disgusting.

“They have to be asking themselves so many questions like is it my fault and did I do something wrong?”

The family is gradually rebuilding their lives and they hope by speaking to the Croydon Guardian other families will not have to go through the same ordeal.

The victim’s father added: “We want people to realise that it can happen to you.

“If one person is saved from a terrible ordeal then that would make me happy.

“It’s not a taboo subject and you need to talk to your children about appropriate adult contact.”

Carroll was found guilty at Croydon Crown Court on Tuesday, May 13, of sexual abusing the boy and two counts of breaching his sexual offences prevention order.

He is due to be sentenced on June 16 and has been told to expect a lengthy prison term.

The police response

Detective Chief Inspector Kevin Clarke, from Bromley police’s Jigsaw unit, said: “We are committed to monitoring registered sex offenders; the safety and protection of members of the public is paramount.

"Registered sex offenders are monitored and supervised through management plans devised by the multi agency public protection panels on boroughs.

“The degree of supervision and intrusiveness varies according to the risk posed by each offender.

“We take the matter related to registered sex offenders breaching their conditions extremely seriously.

“Our officers will investigate all allegations and lines of enquiry in order to trace these offenders and bring them before a court.”