A road was cordoned off as police probed reports of a crash between a car and a scrambler bike in Walton.
Officers received reports of the collision near the Carisbrooke Road and Bedford Road junction at 9pm.
When they arrived at the scene there was no evidence of a crash, however.
Detectives are now appealing for details and have not ruled out any collision may have been deliberate.
No injuries have been reported following checks with local hospitals and Merseyside Police said CCTV, forensic and witness enquiries are ongoing.
Detective Inspector Phil Atkinson said: "At this stage it is unclear what happened, although we have information to indicate some kind of collision, but whether accidental or deliberate we don’t yet know.
“If you were in the area around 9pm and saw or heard anything, or live locally and have CCTV or dashcam, please come forward and we will take the appropriate action."
*Anyone with information about what happened is asked to contact Merseyside Police on Twitter (@MerPolCC), on Facebook (Merseyside Police Contact Centre) or by calling 101, with the reference number 20000543606.
You can also contact Crimestoppers, anonymously, on 0800 555 111 or online.
