The son of a man who was fatally stabbed in Etobicoke late Tuesday afternoon has been arrested in connection with his murder, Toronto police confirm.

It happened near Martin Grove Road and Redgrave Drive at around 4:30 p.m.

Police spokesperson Katrina Arrogante told CP24 that the father and son were engaged in “some type of fight” and both sustained stab wounds during the course of that altercation.

She said that the deceased party was already without vital signs by the time paramedics arrived on scene.

Paramedics started life-saving efforts and were planning to transport the 50-year-old man to hospital via emergency run but ultimately pronounced him dead at the scene, Arrogante said.

The second male victim, meanwhile, was located in a vehicle on Highway 401 near Islington Avenue after reportedly fleeing the initial scene of the stabbing. Investigators say that officers were responding to reports of a multi-vehicle collision in the area when they found a 20-year-old man with injuries.

The officers extracted the man from the vehicle and transported him to the hospital.

The man’s injuries are considered serious, according to Arrogante.

“One female had also been injured from trying to disrupt this fight,” Arrogante said, though she did not specify the severity of her injuries.

The deceased has been identified by his brother as Ameer Saib.

His brother, Abdool Saib, told CP24 that he was “bewildered and shocked” when he heard about the stabbing.

“At the end of the day, this is something you cannot deal with,” he said. “My brother is lying behind me in an ambulance dead. My nephew, 20 years old, is in the hospital and apparently something happened in that apartment.”

No charges have been laid thus far in connection with this investigation.

Detectives have confirmed that Ontario’s Special Investigations Unit (SIU) is involved in the investigation. The SIU is an arms-length agency that investigates incidents involving police where someone is killed, seriously injured or accused of sexual assault.

The eastbound collector lanes of Highway 401 have been closed between Kipling and Islington avenues as police investigate at that second scene.

This is the city’s 76th homicide of 2018.