The fire broke out late Sunday afternoon at the car park located next to the Echo Arena, hours before an international horse show.
“Initial investigations indicate that an accidental fire within a vehicle caused other cars to ignite,” a statement by Merseyside police said.
It said “all vehicles parked in the car park have been destroyed.”
The fire services said 12 fire engines fought the blaze at the car park with a capacity of 1,600 vehicles.
The blaze forced authorities to move horses from the Echo Arena for protection and caused the show’s cancellation. Hundreds of visitors were left stranded with their cars destroyed, local media reported.
The Liverpool International Horse Show was held at the arena, and it was to conclude with the Sunday show that would have hosted 4,000 guests.
“No one has been seriously injured, the force said. It was also reported that no animals were hurt,” the police said.