After sometimes life-threatening stabs against three young men in Düsseldorf's old town, a suspect has turned himself in.
The only 17-year-old teenager is to be brought before a magistrate on Wednesday, according to police and prosecutors.
A homicide detective is investigating attempted manslaughter.
The 17-year-old is said to have stabbed three strangers aged 17, 18 and 22 with whom he had allegedly clashed in the early evening of Carnival Sunday.
On Tuesday, the police released images from a surveillance camera to identify the suspect.
On the same evening, the 17-year-old and an alleged accomplice, also 17, turned themselves in to the federal police.
The companion was allowed to go again.
The murder weapon, according to witnesses and the type of injuries a knife, has not yet been secured, according to the public prosecutor's office.
All three victims are now over the mountain, but some are still in the hospital.
In a second case involving a knife attack, the perpetrator has not yet been caught.
On the evening of Shrove Monday, an 18-year-old was discovered lying in an alley with serious stab wounds.
Before that, he is said to have been bumped into by three young men, hit and finally wounded in the stomach with a knife.
The perpetrators fled, the 18-year-old was operated on.
The police are asking for information.