TORONTO -- A suspect accused in a Brampton crash that left a mother and her three young children dead was fleeing from police at a high rate of speed just prior to the incident, Ontario’s police watchdog confirms.

Karolina Ciasullo, 37, and her three young daughters—Klara, 6, Lilianna, 3 and Mila, 1—were killed shortly after noon on June 18 after their Volkswagen Atlas was struck by an Infiniti G35 near Torbram Road and Countryside Drive.

Brampton crash

The driver of the Infiniti was taken to the hospital and later placed into police custody.

At the time, the province’s Special Investigations Unit (SIU), an arm’s length agency that investigates incidents involving police officers where there has been death, serious injury and sexual assault, was called to the scene

According to a report released late Wednesday morning, a Peel Regional Police officer was pursuing the suspect at the time of the crash.

The SIU said the officer was driving along Countryside Drive around 12:15 p.m. when they noticed a vehicle without a licence plate travelling in the opposite direction at a high rate of speed.

“The police officer made a U-turn and activated his emergency lights,” SIU Director Joseph Martino said in the report. “The offending vehicle continued at a high rate of speed, blew the light at Torbram Road and collided with multiple vehicles. There were multiple fatalities.”

The Volkswagon was struck on the driver’s side and propelled into a utility pole, the SIU said, at which time the pole collapsed on top of the vehicle.

The three children were buckled into safety seats at the time of the crash.

Brampton crash

Investigators say the driver of the Infiniti was travelling at a calculated speed of 152 kilometres per hour.

On Wednesday, the SIU determined there were no reasonable grounds to lay criminal charges on the police officer who was pursuing the driver of the Infiniti.

“He did what one would expect of an officer in a marked cruiser patrolling the roadways who comes across a vehicle without a front licence plate; he intervened with the intention of investigating its driver for a potential traffic offence,” Martino said.

At the same time, Martino added that GPS data shows the officer failed to come to a complete stop at several stop signs during the pursuit, a fact he called “disconcerting” but not grounds for criminal charges.

The driver of the Infiniti, identified by police as Brady Robertson, was originally charged with four counts of dangerous driving causing death in connection with the crash.

Last month, additional impaired driving charges were laid. Robertson now faces four additional counts of impaired operation causing death by drugs.

Robertson has been denied bail on the original four charges and remains in police custody.

The charges have not been proven in court.