The fire at Southview Holiday Park in Burgh Road was reported to Lincs Fire and Rescue at 7.52pm on Friday
Smoke could be seen from around the area and people living nearby were asked to keep their doors and windows closed.
The fire spread across five caravans Lincolnshire Police say they were empty and no casualties were reported. Two caravans suffered total damage and three more have extensive damage.
Crews from Skegness, Spilsby and Wainfleet attended and extinguished the blaze using three hose reels and thermal imaging camera. They left the scene later that evening.
An investigation into the incident was launched on Saturday by Lincolnshire Police, saying they were treating the incident as "suspected deliberate ignition”.
Police announced they had arrested a 13-year-old boy on Monday and said that he had been released on bail.
Investigations into the incident are now continuing. Lincolnshire Police say officers from the Criminal Investigation Department (CID) and forensic staff are carrying out several lines of enquiry.
Police are now appealing for witnesses who may have captured footage not yet viewed, or may have information about the incident to come forward to help with investigations.
If you have any information that could help, get in touch by emailing [email protected], putting incident number 413 of 27 May in the subject line.
Alternatively call 101, quoting the incident number.
If you wish to remain anonymous, you can report via the independent charity CrimeStoppers on 0800 555 111 or online.