A number of people were helped to safety by police officers, following a blaze in the early hours of Sunday morning, June 30, on Rushden High Street.
Fire crews were called to deal with the fire in an enclosed courtyard for flats, near to The Railway Inn on the street, just after midnight.
Sergeant Tony Hopkins, of Northants Police, said two traffic officers were the first responders at the scene and helped to get five occupants of a nearby flat to safety.
High Street, Duck Street and Queen Street, were all closed by police while fire crews worked at the scene. The roads have all since been re-opened.
A spokesman for the fire service said a large quantity of cleaning supplies were involved in the fire.
The blaze has caused moderate smoke damage to a first floor flat.
Fire crews had put out the blaze by 12.45am and were set to return to the scene later in the day to complete safety checks.
The police have said they are not currently treating the incident as suspicious.