Police and the fire service scrambled to the site of the former Mr Pickwick pub in Milton yesterday afternoon (June 3).
Now, officers have confirmed that the group of teens have been arrested on suspicion of arson with intent to endanger life.
The fire occurred between a petrol station and a block of flats, and two crews were needed to tackle the blaze while Milton Road was closed in both directions.
Portsmouth Traffic: M27 between junctions 11 and 12 closed throughout August amid footbridge repairs with A27 diversion in place
Thunderstorms in Portsmouth yellow weather warning: The Met Office forecast for the next three days in city, Fareham, Gosport, Havant and Waterlooville and Hampshire
‘I watched ten years of my children’s lives go up in flames': 'Traumatised' Paulsgrove mum of five launches fundraiser to find family new home after they 'lost everything' in bedroom fire
Police update over alleged violent gang rape of woman at address in Portsmouth
Detectives 'file' investigation into woman's abduction in Rowner after failing to find a suspect
A 13-year-old boy, four 14-year-old boys, and a 15-year-old boy, all from the Portsmouth area, were arrested following CCTV enquiries.
A police spokesman said: ‘The boys have been released from custody but remain under investigation while we conduct further enquiries.
‘We ask the community to not speculate on the circumstances or the identities of those involved, but to please report any information about this incident to us on 101, quoting 44220219825.’