Three boys aged 12, 13 and 14, have been arrested in connection with a fire at a multi-story car park in Northamptonshire.
Dozens of firefighters tackled the blaze at Willow Place car park in Corby on Tuesday night.
Four people - two boys aged 14 and 17 and two men aged 19 and 20 - were arrested that night while police officers were at the scene.
The three latest arrests were made on New Year’s Eve.
All seven have been released on bail, pending further enquries.
Police are appealing for anyone with information about the fire, which started shortly after 6pm, to call them on 101 or Crimestoppers anonymously on 0800 555 111.