A 21-year-old man was taken to hospital this afternoon after he was stabbed in the neck in Balga.
Police are calling for information about his alleged attacker, who was the victim's housemate and is still on the run.
A neighbour called paramedics about 2pm after the 21-year-old Sudanese man ran to her front door covered in blood and pleading for help.
The neighbour said she could see stab wounds in his neck and arm.
"They were fighting in that house across the road. He ran up to my house and said, 'Please, please, call the ambulance,'" she said.
"It was very bad. The blood was all pumping out.
"My little boy looked out the door and said, 'Mum, what's happened?'"
The concrete near Achol's front door is covered with blood and there is a blood-soaked shirt lying on her front lawn.
"I'm going to someone else's house tonight because I have little kids, but I don't know how long it will be," she said.
The victim is in a stable condition at Royal Perth Hospital.
His alleged attacker was also a young Sudanese man.
A police spokesman said detectives knew who they were looking for but would appreciate any information on his whereabouts.
Anyone with information is asked to call Crime Stoppers on 1800 333 000.