A 16-year-old who bit a woman on the groin during a late night sex attack on Hampstead Heath is facing jail for a series of violent robberies and sexual assaults.

The youth, who cannot be named for legal reasons, violently robbed two women before groping them in the Parliament Hill area between August 5 and August 8, a court heard on Monday.

His second victim was also bitten through her shorts after she was punched to the ground as she walked across the Heath at night.

Later that day, he went on to rob another woman and attack a man with a claw hammer, Louis Chang, who gave chase after him.

The youth had admitted robbing the women and causing actual bodily harm to Mr Chang last month, but denied touching two of the women sexually.

But district judge Gill Allison found him guilty of two sexual assaults on females following a trial on Monday at Highbury Corner Youth Magistrates’ Court.

Det Sgt Richard Greenwood, who led the case, said: “I’m happy for the victims who were young women who were accosted late at night in very serious circumstances, and now he’s been found guilty, I’m glad for them. Hopefully Hampstead Heath will be a little bit safer now.”

In the first attack on August 5, the court heard how the teenager attacked a female jogger as she ran on the Parliament Hill Athletics Track.

He pushed her to the ground before taking her iPhone 4 from her hand and touching her sexually.

The anonymous victim told the court: “I said, ‘please don’t touch me, please let me go.’”

She claimed he cycled past her and threatened to orally rape her.

He denied this in the dock, and said he was only searching her pockets for money. But Judge Allison dismissed the argument.

In the second attack on August 8, the court heard the youth cycled aggressively close to the victim.

There was a furious exchange of words, ending in the woman telling the youth to “f*** off”.

The youth, who lived in supported housing in Camden, later told the court: “My mind just blew.”

He then jumped off his bike and punched the woman in the back of the head, knocking her to the ground. She told him: “Take what you need”. He then touched her sexually.

The victim told the court: “At that point I thought it was more sinister. I thought that he was not trying to just rob me because I had just offered him all my stuff.’”

He then bit her on the groin before running off with a cool bag she had been carrying.

The youth denied biting her, but forensic scientist for the Metropolitan Police Andrew Bell said the evidence supported the victim’s account.

In the dock, the youth wept and said he would never sexually assault a woman because his mother had been raped.

But Judge Allison said the two victims had been “truthful” and “convincing”.

The youth will be sentenced for two sexual assaults, three robberies, possession of an offensive weapon and causing actual bodily harm at Blackfriars Crown Court on a date to be fixed. He is expected to be jailed for upwards of two years.