Firefighters arrived on scene at Kings Dock around 4.50 p.m. (11.50 a.m. ET) to tackle the blaze involving "a number of vehicles.""Initial investigations indicate that an accidental fire within a vehicle caused other cars to ignite," Merseyside Fire and Rescue Service said in a statement.Authorities said that no one was believed to have been seriously injured. Some surrounding buildings were evacuated as a precautionary measure. The fire service warned residents and local businesses to keep doors and windows shut due to smoke. It advised people to stay away from the area.Witnesses described the fire as "unbelievable." Car windows could be heard exploding. Sue Wright, wife of former England footballer Mark Wright, told Britain's Press Association of fleeing the car park as "an old car exploded.""We've lost everything because our car was right next to the car that exploded. My handbag was in it, our cards, cash, everything. We just grabbed the keys and ran."Wright said cars were "just popping every couple of seconds."The Echo Arena, located next to the car park on the waterfront, had been hosting a four-day international horse show. After the fire broke out, animals were evacuated from the venue and the final evening's events were canceled. "The flames and the smoke was unbelievable," said 44-year-old Kevin Booth from Manchester who was visiting the venue with his family for the horse show. "People were saying that they would just wait and get their cars back. I thought, 'Have you seen the fire? Are you joking?' It was frightening, we could hear the bangs of car windows exploding."On Monday morning, Merseyside Police said 21 fire engines were still battling the blaze, with the fire service adding that the fire is now contained to the car park. "All vehicles parked in the car park have been destroyed," police said. They urged owners to contact their insurance companies."We are likely to be engaged at the scene for several hours and further investigation will follow firefighting action," Merseyside Fire and Rescue Service said in an update Monday.Liverpool City Council announced it had opened a reception center nearby for anyone unable to get home or in need of temporary shelter. Organizers confirmed all horses were safe following the incident while Aintree International Equestrian Center opened its stables overnight for horses in need of accommodation.The Liverpool International Horse show said in a statement it had looked into rescheduling the event for Monday "but unfortunately this has not proven possible." Mayor of Liverpool Joe Anderson took to Twitter to express his gratitude to the community for their offers of assistance."Thank you all so much for your offers of assistance absolutely brilliant response overwhelming, those caught up in the aftermath were so appreciative. Please stop now all sorted. #soproudofyou," he wrote.