DUTCH police still haven’t figured out the nationality of the migrant accused of stabbing to death 17-year-old Lisa in Amsterdam.

The unnamed suspected allegedly followed the teen on her way back from a night out and murdered her in the street as police helplessly listened on.

He appeared in court on Monday – also suspected of rape and sexual assault relating to two other incidents.

Public prosecutors said: “His identity has not been 100 percent established.

“Therefore, his age has not been established either,” although he is reportedly aged 22.

A magistrate detained the suspect for a further two weeks to give time for the complex investigation.

Officers were said to be on the line when 17-year-old Lisa was ambushed in the early hours of Wednesday as she cycled home from a night out in the capital.

Insiders told Dutch outlet De Telegraaf that police heard her desperate final moments after she called them to say she was being followed.

The teen, from Abcoude, realised she was being trailed and called the emergency line 112 at around 3.30am on Wednesday.

According to insiders, the call lasted until the moment she was attacked.

Police reportedly heard noises, shouting, and then the line went dead before her phone was quickly traced.

Officers rushed to the scene after tracing her phone – but found her lifeless body in a ditch near Holterbergweg just 30 minutes later around 4am.

Lisa had suffered numerous serious stab wounds to her body and neck.

Detectives say Lisa was attacked by a man also on a bicycle and killed with “severe violence”, local outlet HLN reports.

Cops found a knife was near the migrant centre where the man was staying – and are probing whether it could be the murder weapon.

It was revealed on Friday that the man is suspected of two further crimes – both sex attacks on women.

A woman was brutally raped on the night of August 14.

She was yanked from a path in the Weesperzijde neighbourhood just three miles from where Lisa was found and sexually abused – leaving her needing hospital treatment.

A description of the perpetrator was provided as a dark-skinned male, around 20 years old and around 1.7m tall.

A major investigation was launched to catch the sicko – with Lisa murdered a few days into the probe.

Police reportedly made a link between the two cases from the outset, and gradually the net closed around the suspect.

He was announced as the prime suspect in the gruesome rape on Thursday, and on Friday prosecutors declared him the the suspect in Lisa’s murder as well.

Later on Friday, police linked the man with a third alleged crime – a sexual assault attempt on August 10.

This was initially reported as a street robbery, but later treated as an attempted sexual assault.

The suspect was cuffed by cops at the hostel, operated by the City of Amsterdam, where he was staying.

Sources told De Telegraaf that Lisa’s entire ordeal took place in less than ten minutes.

Lisa had only left Leidseplein on her electric bike half an hour earlier after a night out with friends.

Dutch cops have not explicitly confirmed whether the man Lisa reported is the same person who killed her – but investigators suspect only one perpetrator, making it highly likely they are the same individual.

A police spokesperson said: “The investigation so far indicates that the victim left Leidseplein in Amsterdam around 3.30am.

“On her way to Abcoude, she cycled along Holterbergweg and was attacked there by a man who also owned a bicycle.

“The victim contacted the police dispatch centre about this incident.

“Officers subsequently found her there around 4.15am.”

Police continue to appeal for witnesses, especially three specific road users — a scooter rider, the occupants of a light-coloured van, and someone driving a Biro microcar — who were on Holterbergweg shortly after Lisa was killed. 

The case has provoked national fury after it emerged that the main suspect — a 22-year-old asylum seeker — had already been arrested days earlier over separate allegations of rape and assault.