A teenager has been arrested after allegedly stabbing his friend in the stomach with a samurai sword during a sleepover at a house in Herriman, Utah.
Police have speculated that the unidentified 17-year-old may have suffered a psychotic breakdown before the attack.
The victim, also 17, was attacked at around 6am on Saturday morning, when he was stabbed through the torso.
It is not known if he was sleeping at the time of the attack.
“It was a tragic, very uncommon and strange event, Police Lieutenant Lex Bell told local media.
“The question of the day is: Why did this happen? The two had been friends for years, as I understand it.”
Mr Bell described how the victim's father found the suspect trying to get another weapon to stab the victim again, so the father grabbed the assailant and there was “a physical altercation.” Family called the police and an officer soon turned up and fired a Tazer at the attacker in an attempt to pacify him.
“He was forced to grab onto the suspect and try to physically restrain him and get him into handcuffs, but the suspect fought extremely hard,” Mr Bell said.
“It turned into quite a fight.” Attending firefighters who were waiting outside - as per protocol - heard the struggle and decided to go into the house.
“They could hear how out-of-control this fight was,” said Mr Bell.
“Thankfully they made the decision to go in anyway [ignoring procedure], and by doing that they absolutely saved the life of our victim and very well could have saved the life of the suspect. Who knows what direction that could have gone.”
He added: “We're extremely grateful to the Unified Fire Authority for ably coming into a situation that was not secure and risking their own lives to save our victim, our officer and that family.”
It was only with the help of the firemen the attacker was subdued and first aid was provided to the victim, who was later taken to hospital in an “extremely critical condition”.
Police said drugs were being looked into as a possible cause for the incident.
“He was obviously having some sort of psychotic episode,” said Mr Bell.
The Independent