A house rammed by a car before the fatal A66 crash in Middlesbrough belonged to the father of a teenager who died in the incident.
Cole Worthy, 17, was one of five young men who died when a Volkswagen Passat travelling in the wrong direction hit a Cleveland Police armed response vehicle, also killing two police officers.
Before the crash at 03:39 BST on Saturday, police had received multiple reports of two cars driving dangerously around the town and a Volvo XC60 was seen ramming properties.
The BBC understands that, after his father’s home was rammed, Worthy and the four others set out in the Passat. Police said they were linking the activities of the Volvo XC60 and the Passat.
There is no suggestion Worthy’s father was involved in criminal activity.
PC Tom Clough, 38, and PC Matthew Blades, 37, died in the crash, as did Michael Robert Cahill, 23, Jacob Matusiak, 23, Makai Saddington, 18, Theo Rae, 17, and Worthy.
The Independent Office for Police Conduct said officers had been pursuing the Passat for almost seven minutes after it was connected to earlier alleged criminal activity, but the pursuit was abandoned 10 seconds before the crash when it turned on to the dual carriageway.
Both vehicles were operating with cloned number plates but were picked up by automated number plate recognition technology.