A woman stabbed and wounded six people in a bus in western Germany on August 30 evening, police said, Report informs referring to DW.
They had earlier said a total of five were injured in the incident but later revised the figure.
The 32-year-old suspect, a German national, was arrested after the attack in the town of Siegen.
At least 40 people were on the bus travelling to a city festival at the time of the incident.
Three of the victims are in a life-threatening condition, according to authorities.
Police are investigating the motive behind the crime. They said there were no indications that it was a terrorist attack.
Police appealed to citizens "not to spread false reports" on social networks or other channels.