A 15-year-old boy is being treated for life-threatening injuries after being stabbed more than 20 times.
The teenager was attacked in Preston Gardens, Luton, at about 02:10 BST.
Det Insp Jerry Waite described the violence as “horrific” and is appealing for witnesses.
“The victim received more than 20 stab wounds in this shocking incident and is now fighting for his life,” Det Insp Waite said.
“It’s absolutely vital that anyone who has any information about this incident, no matter how minor it may seem, gets in touch with us.”