Following a large blaze at a former surgery in Aylesbury on Friday, Thames Valley Police have arrested four people.
The blaze started at the former Meadowcroft surgery in Jackson Road just after 2.45pm on Friday (25/8).
Buckinghamshire Fire & Rescue Service extinguished the fire in the early evening.
Two people were treated for the effects of smoke inhalation, but nobody else was injured.
A cordon was in place while the fire service dealt with the blaze.
Three boys, aged 15, 14 and 12, all from Aylesbury, and a 14-year-girl, also from Aylesbury, were arrested on suspicion of arson and have since been bailed until 14 November while investigations continue.
Superintendent Clare Knibbs said: “This was a large fire, which I am aware caused some disruption in the local area.
“Thankfully, no-one was injured in the incident, and I would like to thank our colleagues at Bucks Fire & Rescue Service and South Central Ambulance Service for their swift actions.
“I would also like to pass on thanks to the local community for their patience and understanding while the fire was being dealt with.”
Anybody with any information, or who witnessed the incident, is asked to contact Thames Valley Police either online or by calling 101, quoting reference 43230381315.