A man suffered smoke inhalation and burns to his hand in the incident, the fire service said.
Suffolk Police says a man in his 30s has died after a collision with a Peugeot 307 on the B1063.
Suffolk Police arrests two more prisoners after a the death of an inmate in January.
Suffolk crews are sent to the category C men's jail.
Officers say the investigation relates to banned goods being taken into wings within the jail.
The tennis balls are retrieved by dogs working for the police and prison service.
Up to 50 firefighters tackle the blaze, with one engine travelling 60 miles to get there.
