What we know - and what we don't Why was the Winterthur stabber on the loose again?

Why was a man known to the police able to injure three people with a knife in broad daylight at Winterthur station? Much is known, but the most important questions remain unanswered. An overview.

The knife attack at Winterthur station moves Switzerland. Hours later, the police and government announced that the man arrested had been known to the police for years and had a criminal record.

blue News provides you with an overview of what is known about the crime and the perpetrator - and what is not.

On Thursday morning at 8.28 a.m., a man stabbed three men with a knife at the north end of Winterthur station, seriously injuring one of them. Afterwards he is said to have shouted "Allahu akbar".

Five minutes after the attack on the first man, Winterthur police officers arrest the perpetrator.

Knife attack in WinterthurFederal criminal police knew about the suspected perpetrator two days before the attack

In principle, the man is considered innocent until his conviction. However, in view of the eyewitnesses and the statements of the police, there is no doubt that the 31-year-old man, whose name was given by cantonal councillor Mario Fehr at the media conference, committed the crime.

It has also been confirmed that the attacker is the Turkish-Swiss dual national who had already been convicted of violating the IS ban in 2015. According to police commander Weyermann, he spread IS propaganda.

The later perpetrator grew up in Winterthur and attended school there. As a teenager, he came into conflict with the law during fights and drug offenses, writes Kurt Pelda in the "Aargauer Zeitung". He has been reporting on the Winterthur jihadists for years.

As a teenager, the perpetrator frequented the An Nur mosque in Winterthur, which had become known as a radical place. He is said to have once beaten up worshippers there together with other young people because they were "bad Muslims".

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The perpetrator from Winterthur had spent most of the past two years in Turkey, reported Councillor Fehr at the media conference. Shortly before the knife attack, he had been reported back to Winterthur, where he had grown up and attended school.

On May 25, three days before the attack, he called the emergency number 117 and made confused, delusional statements. Police officers then sought him out and arranged for him to be placed in care and taken to the psychiatric clinic in Winterthur (IPW).

Contact with the authorities, clinic, crimeThe story of the Winterthur knife attacker up to the crime - a chronology

One day later, the 31-year-old escapes from the closed ward of the IPW. The police find him at home - he lives with his parents - and bring him back to the IPW.

On May 27, a doctor assesses him as no longer a danger to himself or others. This puts an end to his deprivation of liberty. The man then leaves the clinic.

The next morning, he attacks three men with a knife.

Security Director Mario Fehr describes it as a "tipping point" before the attack: the evening before, the doctors at the Winterthur Integrated Psychiatric Ward (IPW) assessed the 31-year-old as neither a danger to himself nor to others. He then decided to leave the clinic.

It is not known why those in charge were mistaken about the man's potential danger - based on which findings. Jérôme Endrass, head of research at the Zurich prison system, explained to SRF that the doctors and psychiatrists had no forensic training and did not have all the information. It is intentional that this is the case, he explains.

The IPW announced the day after the crime that it was having its procedures reviewed externally. According to the SDA, the investigation will focus on procedures and responsibilities.

At the media conference, government councillor Fehr stated that the perpetrator had spent most of the past two years in Turkey. He made no statements about what he had done there or who he was in contact with.

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No statements are known from the arrested perpetrator. His past and the shouts of "Allahu akbar" suggest a jihadist motivation, but nothing has been proven. Nothing is known about a possible letter of confession or posts before the crime.

After the attack, the 31-year-old's father told Blick that his son was not a terrorist, but that he was mentally ill and needed help.

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It is also unknown whether the perpetrator planned the knife attack. His officially confirmed mental confusion makes it plausible that he committed the act spontaneously or at least without long preparation. However, nothing is known about this. Not even whether third parties instigated him.