THE parents of a schoolboy who was the victim of a sexual assault at knifepoint have spoken of their son's courage after his teenage attacker was locked up for six years.

The 13-year-old victim thought Ross Wiseman was a jogger when he spotted him in Mill Woods, Chafford Hundred, as he walked home from school at 3.30pm on November 29 last year.

But moments later Wiseman, 17, pulled out a knife with a 12-inch blade from his trousers, and threatened to "slit his throat" and "cut him up" if he did not hand over his mobile phone.

Wiseman, who has a previous conviction for robbery, then ordered the terrified victim to take off his shoes before assaulting him.

The victim fled barefoot, without his school blazer.

Speaking after Wiseman was sentenced at Basildon Crown Court, the victim's father said: "My wife and I are unbelieveably proud of our son.

"The incredible bravery he has shown, not only thoroughout the attack when he thought he was going to be killed, but afterwards when he had the presence of mind to escape when he had the chance.

"He did not flinch throughout the enquiry, even though he had to make several trips to the police station and undergo a medical examination.

"It is purely because of his bravery and strength that the police were able to catch and convict Wiseman and stop anyone else being a victim."

Cyrus Shroff, prosecuting counsel, said just over a week before the attack, Wiseman had robbed two 15-year-old schoolboys at knifepoint in the same area.

Judge Christopher Mitchell lifted an order so Wiseman could be identified and told the defendant: "Both sets of offences were committed in the same Mill Wood area of Chafford Hundred and both sets of offences were perpetrated on boys younger than yourself."

Judge Mitchell, who also ordered that Wiseman be placed on the sex offenders register for the rest of his life, said it was clear from the psychiatrist who examined him that he represented a significant risk to the public.

Det Supt Simon Dinsdale, who was in charge of the investigation said: "Crimes such as this are extremely rare. Detectives were able to identify and arrest the man responsible very quickly and put him before the court.

"I am pleased the defendant pleaded guilty and hope the victim and his family can now start to move on with their lives."

Wiseman, of Buckles Lane, South Ockendon, pleaded guilty to the attack, three counts of robbery and one count of handling stolen goods at an earlier hearing.