Windsor Fire is investigating a 'suspicious' fire on Monday, that has led to an arrest and has sent one person to hospital.

The fire happened overnight at a home on Arthur Road. Windsor fire said it involved a vehicle and a garage at the back of a home, and a shed. 

Police have arrested one person, and a second person of interest is in critical condition at a London hospital. Police say that person has burns on 35 per cent of their body. 

Windsor Fire estimates the damage at $100,000. 

The incident is under investigation.