The Liverpool Echo has the story on its web site – see link below:-
It’s the section of Northway between the Hall Lane and Dover Road/Liverpool Road South junctions and the accident seems to have been on the southbound carriageway.
It seems that the Police were chasing a stolen car just before it was involved in the crash. The vehicle was travelling on the wrong side of the road. The driver of the stolen car ran from the scene but was arrested I understand.
We can only hope that the seriously injured person pulls through.