BRAMPTON, Ont. -- A police force west of Toronto says its first three homicide victims of the year all died within the same night in two unrelated domestic incidents.

Peel Regional Police say the first two victims, a 32-year-old woman and her 60-year-old mother, were found in a home in Brampton, Ont. late Friday evening.

Const. Rachel Gibbs says both women died of stab wounds, while a child in the home was found unharmed and taken into protective custody.

Gibbs says the 29-year-old husband of the youngest victim has been charged with two counts of second-degree murder.

Police were called to a home in nearby Mississauga, Ont. hours later on Saturday morning, where Gibbs says a 61-year-old woman was found dead from stab wounds.

The woman's 61-year-old husband has been charged with first-degree murder.

Gibbs said the couple's two teenage daughters were also found in the home, one of whom had to be taken to hospital.

Gibbs said she is currently in serious but not life-threatening condition. Her sister was unharmed.

Ontario's police watchdog was also called in to probe the Mississauga case, Gibbs said.

The Special Investigations Unit said a man was taken to hospital with an undisclosed, serious injury after an interaction with police, but did not provide further details.

The SIU is an arms-length agency that investigates incidents involving police in which someone is killed, injured or accused of sexual assault.

"It was a very tragic night," Gibbs said in a telephone interview. "It was our first, second and third homicide of the year."

Gibbs said there was no connection between the two investigations, describing them as unrelated domestic incidents.