The fire started at around 6am on Thursday 20 July 2023 at the rear of an address in Luton Road near the junction with Bank Street.
Kent Fire and Rescue Service attended and extinguished the blaze which had spread from a carport into an adjoining building.
A family were evacuated from the premises and were taken to hospital to be treated for the effects of smoke inhalation.
Detective Sergeant Hannah Brown, of Medway CID, said: ‘We have been completing enquiries into this incident and are treating the fire as suspicious. Officers are appealing for witnesses who saw anybody acting suspiciously in the area before 6am or running from the scene shortly after the fire started, to contact the appeal line.
‘Motorists with dashcam and local residents with private CCTV are also asked to check for footage that may assist the investigation.’
Anyone with information is urged to contact Kent Police on 01634 792209, quoting 46/129408/23.
You can also call Crimestoppers anonymously on 0800 555111 or complete the online form on their website at www.crimestoppers-uk.org
