Police say a two-year-old Milton, Ont., boy died Wednesday after he was left for a "significant portion of the day" in a family member's car.

Police responded to the call just after 5 p.m. Wednesday in a residential area in Milton.

Halton Regional Police say the toddler's parents were at work, and the car had been driven by an extended-family member.

It’s not known whether heat was a factor in the boy’s death. Outside temperatures on Wednesday afternoon exceeded 30 C with high humidity. No criminal charges have been laid.

The red car, which had been parked just outside the garage of a home, was towed away late Wednesday by police.

The official cause of death will be determined after a coroner's examination on Thursday.

Halton police say the homicide squad is mandated to investigate the death of any child under the age of five.

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