According to the Düsseldorf public prosecutor’s office, it is checking whether the bloody attack that injured four people in a Duisburg gym on Tuesday a week ago was a terrorist act.

A spokesman for the prosecutor told the DPA news agency that the investigations against the 26-year-old suspect came up with corresponding information. Therefore, the Düsseldorf public prosecutor’s office took over the case from the Duisburg public prosecutor’s office. The spokesman did not give any details about the new information.

The television station RTL * reports that photos and videos with an Islamist background were discovered on the alleged perpetrator’s cell phone. However, it is still unclear whether the Syrian is mentally ill. The “Bild” newspaper claims to have learned about the man’s suspicious Facebook account, as well as about “handwritten notes that could indicate Islamist sentiments”.

The Duisburg public prosecutor’s office had previously revised the initial assessment, according to which a 21-year-old gym visitor had been specifically attacked by the perpetrator and the other three men were accidental victims. None of the victims interviewed knew the alleged perpetrator, it said. “Amok sounds so bad. Ultimately, it’s the random selection of victims without specific reasons,” said a spokeswoman for the public prosecutor’s office.

According to media information, the man arrested on Sunday has not yet commented on the crime he is accused of.

On Tuesday a week ago, the perpetrator broke into a John Reed fitness studio in Düsseldorf’s old town and injured the four men there. The 21-year-old is still in mortal danger. Three 24, 24 and 32 year olds also had to be hospitalized with significant injuries. The investigators named a “cutting or stabbing weapon” as the crime tool, possibly a knife or a machete.

Authorities released multiple mug shots of the suspect on Friday. According to witnesses, the 26-year-old was arrested on Sunday in his apartment near the crime scene. He has been in custody since Monday on suspicion of attempted murder.

According to the police and the public prosecutor’s office, the alleged perpetrator applied for asylum in Germany in 2016, saying that before the attack in the gym he had only appeared in two cases of “minor property crimes”. However, both procedures have been discontinued.

* The star is part of RTL Germany.

Sources: , Duisburg public prosecutor’s office (1), Duisburg public prosecutor’s office (2), Duisburg public prosecutor’s office (3), RTL West, “Bild” newspaper, “Spiegel”, DPA news agency