Nicola Courtney, 34, and Lucas Page, three, both from Scunthorpe, were killed in the Friday accident on the A180 in Immingham, North East Lincolnshire.
Specialist officers are assisting their families, according to Humberside Police.
At 9.06 p.m., a white lorry was travelling westbound along the A180 between Stallingborough and Brocklesby.
It collided with a stationary blue Ford Focus that had broken down in the middle of the road.
“The full circumstances of the collision will be established during this complex investigation,” a police spokesperson said. We would ask people not to speculate about the circumstances of the crash.
After receiving several calls about the broken-down car prior to the crash, Humberside Police referred itself to the Independent Office of Police Complaints (IOPC). The police have asked for witnesses to come forward.
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