Officers were called to the property in surrey avenue, yorktown at around 11.15pm by Surrey Fire and Rescue Services after an old TV which had been discarded on a communal stairwell is belived to been set on fire.
All residents were evacuated for a short period of time and four of them were taken to Frimley Park Hospital suffering from smoke inhalation. They were all later discharged with no lasting effects.
The fire, which caused damage to the walls of the property, is being treated suspicious and detectives are working with fire investigators to establish the circumstances surrounding the incident.
Officers are appealing for anyone who may have witnessed any suspicious activity in the area on saturday night or anyone who has any information about who maybe resposible to come forward.
Temporary Detective Inspector Chris Goodman said ” This type of reckless behaviour can put lives and property at risk. Surrey Heath is a safe area to live and i would to reassure local residents that we are doing everything possible to catch those responsible for this crime”.
Anyone with information should call Surrey Police on 101, quoting reference number P12194541 or call Crimestoppers annonymously on 0800 555 111