Angela Merkel is facing a fresh barrage of criticism in Germany over her immigration policy after a teenage Afghan refugee went on an axe rampage.

The self-radicalised ISIS fighter, understood to be Muhammad Riyad, shouted 'Allahu Akbar' as he injured 15 people with weapons on a train in Wurzburg last night before he was shot dead by police.

The attack has added fuel to the heated debate Europe-wide on immigration, Islam and asylum seekers from across the Middle East and Africa after Germany opened its doors to more than a million migrants last year alone.

German chancellor is facing increasing anger in the country over her policies with some newspapers reporting that the attack will boost support for far-right groups.

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German chancellor Angela Merkel is facing fresh criticism from her peers for her immigration policy after a teenage Afghan refugee - Muhammad Riyad - went on an axe rampage

A headline on Germany's Die Welt website said the incident has been 'an accelerant' for the anti-immigrant Alternative For Germany party and the Pegida movement.

The case is likely to deepen worries about so-called 'lone wolf' attacks in Europe and will put political pressure on Merkel.

'In the minds of many people, his arrival is directly linked to Merkel and her liberal refugee policies,' said Frank Decker, political scientist at Bonn University.

Public support for Merkel has risen since Britain voted on June 23 to leave the European Union, helping reverse a fall in her popularity caused by the refugee crisis. But Decker said a Nice-style attack in Germany could quickly end those gains.

'It would boost those who have called Merkel's policies a mistake,' he said. 'Merkel would be blamed.'

Among Merkel's critics is Bavarian Premier Horst Seehofer, who says the influx is more than the country can cope with, according to Bloomberg.

GERMANY'S MIGRANT CRISIS German chancellor Angela Merkel's open-door immigration policy invited more than 1.1million refugees into the country last year. The figure was more than any other EU nation and the majority of migrants were from Syria, followed by Afghanistan, looking to flee poverty and conflict. Bavaria saw a flood of refugees pour over the border from Austria and on New Year's Eve more than 1,200 sexual assaults were reported with gangs of marauding migrant men targeting girls and young women as they celebrated in the streets. The number of refugees arriving in Germany has fallen sharply as a result of the closure of the Balkans migration route and an EU deal with Turkey to stem the flow. In April, May and June, the number was around 16,000 each month, less than a fifth of the tally seen at the start of the year, according to official figures. Critics say Islamic terror groups could have smuggled in fighters with the mass crowds last year. Advertisement

A leader of Alternative for Germany (AfD) said Merkel and her supporters were to blame for the dangerous security situation because their 'welcoming policies had brought too many young, uneducated and radical Muslim men to Germany'.

One man claiming to be a member of the far-right NPD party said: 'Well done Mrs Merkel - how many more of these do we have to have to get you to change your mind about unregulated immigration?'

Bavaria saw a flood of refugees enter Germany through Austria and Eastern European countries.

Merkel's critics believe she underplayed the risks of inviting so many migrants into the country to flee from poverty and conflict.

Bavaria is governed by the Christian Social Union (CSU), sister party to Chancellor Angela Merkel's conservative Christian Democrats, which has been loudly critical of Merkel's welcoming stance toward asylum seekers.

The split threatened the unity of the ruling coalition in Berlin and sent the government's approval ratings plunging.

Although Merkel's popularity has rebounded recently the Bavaria attack is likely to stoke political tensions.

But Bavarian Interior Minister Joachim Herrmann however warned against tarring all asylum-seekers with the same brush.

'It is undisputed that he was a refugee and if he hadn't been there he wouldn't have committed this act,' he said.

'But I don't think that we should make blanket judgements in any way about refugees.'

German police carry the body of the Afghan train attacker is carried from carriage and into a hearse after he was shot dead by police

It is feared Islamic extremist groups could smuggle in fighters into Germany with genuine asylum seekers, says the Wall Street Journal.

Germany let in a record nearly 1.1 million asylum seekers last year - more than any other EU nation - with Syrians the largest group followed by Afghans fleeing ongoing turmoil and poverty in their country.

The number of refugees arriving in Germany has fallen sharply as a result of the closure of the Balkans migration route and an EU deal with Turkey to stem the flow.

In April, May and June, the number was around 16,000 each month, less than a fifth of the tally seen at the start of the year, according to official figures.

Bavaria is governed by the Christian Social Union (CSU), sister party to Chancellor Angela Merkel's conservative Christian Democrats.

The CSU has been loudly critical of Merkel's welcoming stance toward asylum seekers, a split that threatened the unity of the ruling coalition in Berlin and sent the government's approval ratings plunging.

It has also lent support to a right-wing populist party, Alternative for Germany, which was founded as a Eurosceptic protest party in 2013 but now mainly rails against Islam and Germany's refugee influx.

It currently polls at more than 10 percent and is represented in half of Germany's 16 states as well as the European Parliament.

The issuewas heightened on New Year's Eve when 1,200 sexual assaults were reported across Germany as marauding gangs of migrant men targeted girls and young women during celebrations.

A stain of blood and the remains of a bandage lie on the pavement close to where the axe attack happened in Germany

Investigation: Police stand by the regional train on which a teenager wielding an axe attacked passengers

The Afghan refugee who went on an axe rampage on a German train had only been living with his foster family for two weeks and may have been self radicalised after he was found to have made an ISIS flag.

ISIS has released a chilling video of him where he says he will attack the country in revenge for airstrikes against the terror group.

The attacker, who is named in the video as Muhammad Riyad, was gunned down by armed police after fleeing the scene near the city of Wurzburg, 70 miles north of Nuremberg last night.

He is believed to be 17 years old although in the video, he appears he could be much older.

He shouted 'Allahu Akbar' during the incident and the terror group have claimed that he was an 'Islamic State fighter', making it the first ISIS attack in Germany.

As many as 19 passengers needed hospital treatment while two victims are fighting for their lives after being attacked with 'cutting and stabbing weapons'.

An eyewitness said the train, which had been carrying around 25 people, looked 'like a slaughterhouse' after the attack, with blood covering the floor.

Now it has been revealed that police searching the home where he had been living had found an home-made ISIS flag and a note indicating that he had become self-radicalised.

The flag and the note are believed to have been discovered in the house he was living in with a foster family. He had only been staying there a fortnight.

Bavarian interior minister Joachim Hermann said that the teenager came to Germany two years ago as an unaccompanied minor, and applied for asylum in March.

He lived in a home for teenage refugees until he was placed with the foster family.

A 17-year-old Afghan refugee went on the rampage with an axe and a knife on a train in Germany. He was later shot dead by police

The case is likely to deepen worries about so-called 'lone wolf' attacks in Europe and could put political pressure on German Chancellor Angela Merkel, who has welcomed hundreds of thousands of migrants to Germany over the past year.

Meanwhile, the Amaq news agency linked to ISIS released a statement saying the Germany attacker was an 'Islamic State fighter.'

It said: 'The perpetrator of the stabbing attack in Germany was one of the fighters of the Islamic State and carried out the operation in answer to the calls to target the countries of the coalition fighting the Islamic State.'

It was also confirmed that two of those caught up in the attack were in a critical condition and that a Chinese family were among the injured.

Meanwhile an eyewitness, who declined to give his name, said he saw people crawl from the carriage and ask for a first-aid kit as other victims lay on the floor inside.

The onslaught started on the train from Treuchtlingen to Würzburg as the service stopped at Würzburg-Heidingsfeld.

As well as the two critically injured victims, one other passenger is believed to have non life-threatening injuries while 14 others suffered minor injuries or shock.

This morning police officers search for evidence in a field near to the railway station close to Nuremburg

Germany had thus far escaped the kind of large-scale jihadist attacks seen in the southern French city of Nice last week

The attacker was eventually shot dead by police after running from the train.

Mr Herrmann earlier said the perpetrator was a 17-year-old Afghan who had lived in nearby Ochsenfurt. He has not yet been named.

'It is quite probable that this was an Islamist attack,' said a ministry spokesman, adding that the attacker had shouted 'Allahu akbar' (God is greatest).

A police spokesman added: 'Shortly after arriving at Wuerzburg, a man attacked passengers with an axe and a knife.

'Three people have been seriously injured and several others lightly injured.'

The rampage onslaught started on the 9pm train from Treuchtlingen to Würzburg as it stopped at Würzburg-Heidingsfeld

As well as the three critically injured victims, one other passenger is believed to have non life-threatening injuries while 14 others suffered minor injuries or shock

The Bavarian interior ministry confirmed that police had shot and killed the attacker and a special task force has been dispatched from Wurzburg

He added: 'The perpetrator was able to leave the train, police left in pursuit and as part of this pursuit, they shot the attacker and killed him.'

There were no further details on the circumstances of the teenager's death, and police declined to suggest what the motive was for the attack.

'At this time everything is possible,' the spokesman said.

Train services had come to a halt between Wurzburg-Heidingsfeld and Ochsenfurt and a police helicopter circled the area.

The Bavarian interior ministry confirmed that police had shot and killed the attacker and a special task force has been dispatched from Wurzburg. Police believe the attacker worked alone.

The train line near the city of Wurzburg in southern Germany has been closed and police have descended on the scene

The teenager was eventually shot dead by police after he tried to attack them with a 'knife or hatchet'

Joachim Herrmann, the interior minister of Bavaria state, said the attacker was a 17-year-old Afghan who had lived in nearby Ochsenfurt

Germany had thus far escaped the kind of large-scale jihadist attacks seen in the southern French city of Nice last week, in which 31-year-old Mohamed Lahouaiej Bouhlel used a truck to mow down people leaving a Bastille Day fireworks display, killing 84 people in an attack claimed by ISIS.

In May, a mentally-unstable 27-year-old man carried out a similar knife attack on a regional train in the south, killing one person and injuring three others.

Early reports suggested he had yelled 'Allahu Akbar' but police later said there was no evidence pointing to a religious motive. He is being held in a psychiatric hospital.

Germany let in a record nearly 1.1 million asylum seekers last year, with Syrians the largest group followed by Afghans fleeing ongoing turmoil and poverty in their country.

The number of refugees arriving in Germany has fallen sharply as a result of the closure of the Balkans migration route and an EU deal with Turkey to stem the flow.

Police, fire and ambulance crews were all dispatched to the scene of the axe attack this evening