Two grandparents are dead, and their 2-year-old grandson is “seriously” injured, after a 91-year-old driver crashed into pedestrians on a suburban sidewalk, according to police and several local news outlets.

Emergency workers responded to the scene on Coleman Road in Melbourne, Australia, after receiving a report that three people were struck by a vehicle at about 12:20 p.m. local time on Thursday, July 10, per a media release from Victoria Police.

Authorities said a 59-year-old woman was pronounced dead at the scene and a 60-year-old male, who was transported to a local hospital with “life-threatening injuries,” later died. A 2-year-old boy was taken to a hospital with “serious injuries,” the release added.

A 91-year-old female driver was treated for “minor injuries.”

Authorities said the driver lost control of the vehicle before striking the pedestrians, and she then drove through a fence and came to rest at a park bench.

An investigation into the incident is currently ongoing, though Victoria Police told PEOPLE that they have not yet interviewed the elderly driver.

The victims were a married couple, and the toddler was their grandson, according to a report from the Daily Mail.

A witness who heard the crash said that she came out of her house following the collision and saw the 60-year-old man lying on his back in her driveway.

“I saw this gentleman fully clothed on his back, bleeding a little bit from his nose. And very bad, heavy breathing,” she told News 7.

“And then later on, we discovered that the little baby had been thrown right over there,” the eyewitness added, motioning to a section of grass on the side of the road. “And he was crying. One of the ladies [nearby] picked him up, and he just held on to her.”

In a July 10 press conference, Victoria Police Road Policing Command Superintendent Justin Goldsmith said that the driver was “terribly shaken” after the incident and was taken to a local hospital for assessment.

Goldsmith additionally said that it is currently unclear whether the driver had experienced a medical episode that may have contributed to the accident, per 9 News.