Details have emerged of another sex attack in the city, which detectives are linking to an hour-long crime spree that included a rape, two robberies and an assault.

A man has been arrested in connection with the attacks - and police are also looking into a sexual assault on a woman at about 4.30am in Riverside Road as she walked towards Norwich's railway station.

It comes as an investigation has been launched following a rape, two robberies and an assault which happened in Norwich between 6.39am and 7.38am yesterday morning.

Detective Inspector Chris Burgess, from Norwich CID, said: 'What we're looking at is we've had a number of attacks across the city.

'We're now looking at a sexual assault, a rape, two robberies and an assault.

MORE: Video footage shows arrest of man suspected of Norwich crime spree, in which a woman was assaulted and raped, two people were robbed and another woman was assaulted

'They happened during a short space of time, an hour to an hour-and-a-half, across the city.'

A 22-year-old man was arrested at the train station in connection with all of the incidents and is currently awaiting questioning.

Det Insp Burgess said reports of an alleged sexual assault in the Riverside Road area only came to light after details of the initial attacks were made public.

He said: 'We've since had another call of sexual assault. We think that happened before the other attacks.

'We believe that was around 4.30am. She was walking along Riverside towards the train station.'

Officers were first called to Ten Bell Court at 6.39am to reports a woman had been assaulted and raped. The woman is being supported by specially trained officers at the Sexual Assault Referral Centre (SARC).

MORE: Norwich crime spree: Ten Bell Court residents' shock as detectives continue to investigate rape, two robberies and an assault

Det Insp Burgess said they believed the woman, who is not thought to have known her attacker, had been in Chapelfield Gardens but was 'dragged off the street' and to the Ten Bell Court area where she was then raped before the suspect left on foot.

He said bearing in mind the time of day and the fact the woman was thought to have been dragged to where the alleged rape happened, police were really keen to speak to anyone who might have seen anything unusual to come forward.

'It's vital that anyone who saw or thinks they saw anything calls us.'

Anyone with information should call police on 101.