It comes as first person arrested in connection with Cologne sex assaults

A migrant allegedly sexually assaulted a 25-year-old victim and told her that 'German women are just there for sex' after approaching her as she walked home from a railway station.

The man, who is said to have recently arrived in Dortmund, told the woman he assumed German women are 'just for sex' after offering money to sleep with her when he followed her in the street.

According to police reports, the refugee was allegedly part of a group of men who approached the young woman and hurled 'filthy' insults at her as she walked home from Dortmund Hauptbahnhof railway station in the early hours of yesterday.

The fresh claims came as the first person was arrested in connection with the wave of sexual assaults in Cologne on New Year's Eve.

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A migrant allegedly sexually assaulted a 25-year-old victim and told her that 'German women are just there for sex' after approaching her as she walked near Dortmund Hauptbahnhof train station (above) in the early hours

The migrant who approached the young woman in the latest incident apparently began following her before offering her money in exchange for sexual intercourse.

She declined, and he is then said to have told her he had only just arrived in the city and assumed 'German women are there for sex' before sexually assaulting her through her blouse and trousers.

According to the Daily Express, she managed to run off and alerted the police – who are now appealing for witnesses to the incident in a bid to trace the suspect.

It comes as it emerged that the first person to be arrested in connection with the string of sexual assaults in Cologne over New Year had been detained at a refugee home in the town of Kerpen.

The 26-year-old man, from Algeria, was held on suspicion of sexual assault and stealing a mobile phone at the weekend, according to prosecutor Ulrich Bremer.

Two other Algerian asylum seekers, aged 22 and 24, were also arrested - both for robbery - in Kerpen and the western city of Aachen respectively, both for robbery, Mr Bremer added.

Police apparently searched their possessions and found two mobile phones – one of which had been stolen during an alleged sexual assault, and another which was the result of pick-pocketing.

The first person to be arrested in connection with the string of sexual assaults in Cologne on New Year's Eve has been detained at a refugee home in the town of Kerpen. Pictured: Crowds outside Cologne train station

Earlier, it was revealed that three teenagers – all of North African origin – had been arrested in connection to the alleged assault of two transgender women in Dortmund.

Named as Yasmine and Elisa, the two victims said that they were verbally abused and threatened with stones by the men near the city's main train station last Monday.

Elisa, 37, and Jasmin, 50, said that the men spoke to them in Arabic and said they needed to stone 'such people' under Shaira Law, according to Breitbart.

'Within seconds we were tossed around…and they took stones from a gravel bed on the corner and threw them at us,' said one of the alleged victims.

A passing police officer is said to have witnessed the incident and arrested the two men.

There is growing concern in Cologne and Dortmund about Germany's ability to integrate migrants following the string of sexual assaults during New Year's celebrations.

The number of people accused of committing crimes in Cologne at New Year now stands at 21, of whom eight are in detention.

Residents near Cologne's main train station - where hundreds of women were groped and robbed by a throng of mostly Arab and North African men during New Year's Eve - have held protests (above) against the assaults

Almost three weeks after the incident a total of 838 people have filed criminal complaints, including 497 women alleging sexual assault.

Some of the victims have jointly filed a single complaint, so that the number of alleged crimes stands at 766, of which 381 are sexual offences, including three rapes.

The scale and nature of the crimes in Cologne, coupled with police descriptions of the perpetrators as being part of a large crowd of drunken men of 'Arab or North African' origin, has fanned the debate about Germany's approach to migration.

Almost 1.1 million asylum-seekers arrived in the country last year, many of them from countries where women face greater discrimination than in Germany.

While the incidents were seized on by those in Germany who had already argued for stricter immigration rules, left-wing parties have also voiced concern.