Detectives investigating this incident have issued an urgent appeal to locate a potential key witness.
The man they are urging to come forward is believed to have witnessed the violent incident and fatal collision after being dropped off by at taxi on Haxby Road at about 1.45am.
It is understood that he had got a taxi fare to the location from Duncombe Place in York at about 1.30am.
The man spoke with an Irish accent and officers think he could have important information to assist the investigation.
If this is you or you know who he is, please contact North Yorkshire Police immediately on 101, select option 2, and ask for York CID, extension 2453. Or email YorkCID@northyorkshire.pnn.police.uk