A woman has described how she came to the aid of a teenage girl who was threatened with a knife in a terrifying Norwich street attack.

A 17-year-old City College Norwich student, who does not want to be named, had been cycling with her 20-year-old boyfriend on Mile Cross Road, Norwich, when they were showered with verbal abuse by a group of young people.

The victim was taunted about her weight before she had a knife held to her throat and her boyfriend was slashed in the arm as he got the attacker off.

The incident happened at about 4.50pm on Thursday, February 28 and was heard by a number of people.

Michelle Farrow, who lives near to where the attack happened, came to help when she heard what was happening.

The 43-year-old said: 'My boys were upstairs and heard a lot of shouting so I went out to see what was going on. My boys had said 'Mum, there's someone fighting outside' so I went out.'

She said she saw the suspect and three girls run off but was told what had happened and went to help the girl who was on the floor.

She said: 'I helped the girl get up. I think she was in shock. She was in a real state. I stayed with her until the police came.'

She described how the victim's boyfriend had a 'small cut' and 'blood down his arm'.

She said he had been trying to protect his girlfriend when he was hurt.

She said she was shocked about what happened because the incident happened in 'broad daylight and you don't expect that'.

The teen previously told this paper that she was now so terrified that she no longer wanted to leave her home.

Police are appealing for witnesses to the incident and have urged anyone with information about the attack to call 101.