A 12-year-old boy is dead and his father has been shot by police following an altercation at a cricket oval in Melbourne's southeast.
Police say the man, who is currently in the Alfred Hospital in a life-threatening condition, came at officers with a knife after they were called to the scene in Tyabb, near Hastings, about 6.30pm (AEDT).
Commander Doug Fryer said four officers used capsicum spray in an attempt to subdue the man before the shot was fired.
"We've had an absolute tragedy here tonight," Commander Fryer said from the scene.
"It's a horrific scene."
Young children are among the witnesses police are speaking to after violence interrupted their evening cricket training.
The mother of the boy was in the vicinity at the time. She is said to be in shock.
"It's obviously shattering," Commander Fryer said.
"His mother is clearly absolutely distraught and our thoughts and prayers go out to her and the extended family."
Commander Fryer said a number of people were present when the incident occurred and he urged anybody who hadn't spoken to police to contact Crime Stoppers.
He said inquiries were still being made in relation to the exact cause of death of the boy, who he confirmed was a local.
An Ambulance Victoria spokeswoman earlier told AAP paramedics had treated the boy for head injuries and that the man had been flown to the hospital with serious chest injuries.
Commended Fryer said a single shot was fired into his chest after he ignored police attempts to get him to put down his knife.
