A boy, 15, living at centre, arrested on suspicion of murder is from Somalia

The mother of a Swedish woman allegedly stabbed to death by an asylum seeker last night declared her country was 'not safe' any more.

Sweden is one of the main destinations for migrants entering the EU and police have warned they cannot cope with the tide of migrant-related crime.

Chimene Mezher described her daughter Alexandra, 22, as an 'angel' devoted to helping some of the hundreds of migrant youths who have come to her home of Molndal without parents.

Psychology graduate Miss Mezher - whose parents fled Beirut more than 25 years ago - was stabbed in the back and thigh on Monday in a block of flats housing ten youths aged 14 to 17.

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Tragedy: Alexandra Mezher, pictured right with her best friend Lejla Filipovic at their high school graduation in 2012, died after being stabbed at her place of work - a care home for unaccompanied child refugees

Pride of the family: Social worker Miss Mezher, 22, a Christian whose parents are from Lebanon, is pictured at her university graduation in June 2015 where she studied psychology

Inspirational: Dedicated Miss Mazher, who was planning on going back to university to do a masters, had been working with refugee children at the centre (pictured) since last autumn

A 15-year-old boy, described as Somalian, is being held on suspicion of murder, and prosecutor Linda Wiking is expected to announce the official arrest on Wednesday.

Officers in Molndal say they have had to ignore lesser offences such as drug-dealing because they are so overrun by migrant crime, with gang fights and violent assaults.

And in capital Stockholm police this week warned that the capital's main train station was 'overrun' by gangs of Moroccan street children 'stealing and groping girls'.

Swedish police revealed they have sent plain-clothes officers to monitor swimming baths in Stockholm after increased reports of sexual harassment of girls and women.

Last night it was also claimed police had been forced to flee after being attacked by a mob of asylum seekers as they tried to relocate a ten-year-old boy amid allegations he had been 'raped repeatedly' at a refugee centre.

The country – with a population of 9.8million – took in more than 160,000 asylum seekers in 2015, with 35,369 of them unaccompanied minors.

Held: SiS ungdomshem Fagared, the youth detention centre in Molndal where the 15-year-old Somali boy accused of murder is believed to be currently held

Murdered: She was stabbed to death while working a night shift alone at the centre for migrant children in Molndal, on Sweden's west coast. A boy, 15, from Somalia, who lived at the centre, is in police custody

Full of life: Miss Mezher (pictured second from left) had only worked at the child migrant centre since the autumn. She was stabbed to death on Monday at 8am

Search: Detectives were at the migrant centre which houses children aged 14-17 searching for clues. Police today praised two hero teenagers who held the knifeman down until they arrived

Tribute: Flowers and candles have been left outside the housing for unaccompanied migrants in Molndal, near Gothenburg, where Miss Mezher was killed

'SOMETHING SERIOUS WILL HAPPEN': STAFF WARNED OF ISSUES AT HOUSING A YEAR AGO Staff at the Swedish migrant centre where social worker Alexandra Mezher was stabbed to death warned of that could not cope with looking after the troubled adolescents a year ago, it has been claimed. A therapist predicted that something ‘serious’ would happen at the juvenile asylum seekers home in Molndal, near Gothenburg, due to a lack of staff but was ignored, Sweden’s Göteborgs Tidning newspaper reported. Alexandra Mezher had worked a night shift on her own at the Molndal migrant centre when she was ambushed and stabbed. Göteborgs Tidning reported: ‘In December 2014 a therapist at the newly founded juvenile asylum seekers home in Molndal called the Department for Health Care and sounded the alarm about problems at the accommodation centre where Alexandra Mezher was killed on Monday. ‘She said she spoke on behalf of other members of staff who all complained that they were extremely understaffed and stated that they often had to work alone, contrary to best work practice.’ ‘So far nothing serious has happened, but it will do,’ the therapist, who asked not to be identified, told Göteborgs Tidning. ‘The staff has talked with the management plenty of times, but they will not help. The management is not listening.’ However the centre was the subject of an unannounced inspection by the Department for Health Care three weeks later, the newspaper claimed. But the Department for Health Care review found no deficiencies in the service carried out at the centre. Advertisement

Yesterday Miss Mezher's mother, 42, said: 'We left Lebanon to escape the civil war, the violence and the danger. We came to Sweden where it was safe, to start our family. But it is not safe any more.

'And I just want to know why… why Alexandra? She wanted to help them, but they did this. I just want answers.'

Her husband Bourous, 45, moved to Sweden from Beirut in 1989 and built up a pizza business. Mrs Mezher, who has three sons, said: 'She was not just my daughter, she was my angel. She was a just and fair human being. There were so many who loved her. She was my daughter, my friend.'

She blamed Swedish politicians for a dramatic rise in immigration in Molndal, a suburb of Gothenburg, where a population of 60,000 has grown by 8,000 migrants in less than a year – 4,000 of whom are unaccompanied children.

The incident comes amid rising tensions over migration in Sweden. The number of threats and violent incidents at asylum facilities doubled between 2014 and 2015 and police have called for more resources.

Visiting Molndal, Swedish prime minister Stefan Lofven said: 'This is a tragedy. It is a terrible crime. I think that a lot of people in Sweden feel a great worry that there might be more similar cases after Sweden took in so many unaccompanied children and youths.'

Miss Mezher had been working at the housing block in Molndal since September. Despite rules that staff should work in pairs, she had reportedly worked alone overnight and was attacked half an hour before her shift was due to end.

Police praised the actions of the other children in the facility, hailing two 'heroes' who overpowered Miss Mezher's attacker.

A spokesman said the 15-year-old was being held in a police cell last night and would go to court as an adult suspect.

He said: 'We don't know anything about the boy's family. We have not even established his identity with a 100 per cent certainty yet.'

Police said Tuesday afternoon the forensic investigation of the scene of the crime is not yet completed, and that there are still question marks regarding the reason behind the attack.

Seven witnesses, all residents at the housing, have been moved to another accommodation and have all been interviewed by police.

Hard working: Psychology graduate Miss Mezher who was a Lebanese Christian whose parents were from Beirut, was today described by her mother Chiméne as an 'angel'

Poignant: Miss Mezher, a Lebanese Christian, had posted a number 'inspirational quotes' on Facebook confirming her faith

Inspiration: Miss Mezher's Facebook profile give a poignant reminder of the loving, caring person she was. Paying tribute her mother said: 'She was a just and fair human being. There were so many who loved her'

Questioning: A boy, 15, living at the centre, from Somalia, is being questioned by detectives on suspicion of murder. Police have cordoned off the centre as forensics investigate

Scene: Molndal, on Sweden's west coast, where the migrant centre is, has been the scene of rising tension in recent months. Neighbourhood-watch groups have been sent out to prevent teenage girls from being sexually harassed on their way home from the commuter trains from Gothenburg

Miss Mezher's best friend Lejla Filipovic said: 'She gave a lot to others. She didn't expect anything back.

Alexandra was the first person in her family to get a degree and her family were so happy and proud of her. Now they are torn to pieces.'

Relative Charbel Aoen said Miss Mezher's youngest brothers Daniel, ten, and Elias, 17, had hardly spoken 'a single word' since the murder.

He said: 'Daniel is so silent it is scary. He is sad and filled with anger. He can't understand why she was alone in that institution and what her last seconds were like.'

Today,Lofven admitted that many people are fearful of attacks similar to the killing of Miss Mezher, because 'Sweden receives so many children and youths arriving alone'.

ALLEGED TEENAGE KILLER TO BE TRIED AS AN ADULT, SAY POLICE The teenage migrant accused of murdering a young Swedish social worker at a refugee centre will stand trial as an adult, it was revealed today. Authorities in Sweden have taken the unusual step of keeping the 15-year-old suspect in police custody due to the serious nature of the crime. Youngsters are normally sent to a secure children's home following arrest, but the teenager is being held behind bars due to public outrage follow the brutal knife killing of Alexandra Mezher. And he will be held in an adult prison until he goes on trial. 'A person is criminally responsible when they reach 15-years-old in Sweden,' a Gothanburg Police spokesman told MailOnline. 'The boy is being held at the police station. But it is very unusual that children to be kept in custody by the police. 'However the public prosecutor has deemed this as a special case due to the nature of the crime and will ask for the boy to be held in prison until he goes to trial.' The spokesman added: 'He is not known by the police and has not been arrested before. But there is always a variable of uncertainty about these kids identity. 'We don´t know anything about the boy family. We have not even established his identity with a 100% certainty yet.' Advertisement

Home: Miss Mezher was living with her parents, originally from Lebanon, and her younger brothers in Borås, some 40 miles from Molndal

Centre: Miss Mezher, whose family are originally from Lebanon, had only worked at the accommodation for unaccompanied refugee children for a few months

SWEDISH LEGAL PROCESS: WHAT HAPPENS NEXT The prosecutor needs to file an application to the district court within 48 hours after a criminal has been arrested. The application is an appeal to the court to hear whether there are legal grounds to keep the criminal in custody. In this case the boy was arrested early on Monday morning, but the system works slowly so he was not formally arrested until Monday night. This document is a public document with the indicted persons name attached to it. The only reason a prosecutor can use to make this document secret is if the crime involves matters of National Security or Terrorism. There has been a few exceptions over the years when the district court has kept the criminals name a secret. Those cases are usually when there has been a police officer working under cover involved. It is for the indicted persons own security. After the prosecutor has send this application he or she will appear in court with the indicted person who also has a lawyer who speaks ion his behalf. A judge will then rule if the criminal is to remain in custody or be released. These hearings usually take around five minutes and are open for members of the public and pres to watch. Advertisement

Swedish police have today praised the actions of the other children living in the facility, hailing them 'heroes' after they overpowered the boy after he attacked Miss Mezher.

'Two boys held him down. It is a very good intervention. Had he intended to hurt anyone else, then they have prevented that,' said police spokesperson Peter Adlersson.

'It is easy to become injured yourself when intervening in this kind of situation. We are very grateful for these kinds of actions.'

Miss Mezher had only worked at the centre in Mölndal for a few months.

It is is home to ten unaccompanied children aged 14-17, who arrived in Sweden seeking asylum without a parent or a guardian and has provoked unrest.

Neighbourhood-watch groups have reportedly been sent out to prevent teenage girls from being sexually harassed on their way home from the commuter trains from Gothenburg.

Parents have also spoken out against having their children in the same classes as the immigrants.

Two Kurdish migrants were injured yesterday in a gun battle at a migrant camp in Dunkirk. One was shot and the other was stabbed, sources indicated. Both were taken to hospital. The Grande Synthe camp – where 3,000 sleep rough – is to be closed by authorities in three weeks' time.

Clashes: Tensions are rising in Sweden as it struggles to cope with a record influx of migrants and asylum seekers (pictured: An estimated 15,000 people attended a Refugees Welcome rally in Gothenburg last year)