Kent Police was called at 5.45am on Thursday 21 December to a report of a fire at an address in the High Street.
Building evacuated
Officers attended along with Kent Fire and Rescue Service, who evacuated residents from the building and extinguished the fire.
South East Coast Ambulance Service also attended and assessed people for injuries. A woman was taken to hospital with smoke inhalation.
Residents have since returned to the building.
Arrest
Enquiries at the scene led to a man from Margate being arrested on suspicion of arson endangering life. He remains in custody while an investigation continues.
Anyone with information that may assist officers with their enquiries should call Kent Police on 01843 222289 quoting 46/223887/23.
You can also contact Crimestoppers anonymously on 0800 555111, or by using the online form on their website.