A teenager arrested in connection with a series of suspected arsons in Norwich is no longer on bail but a police investigation is continuing.

Beginning in July last year, a series of fires broke out at disused sites in Thorpe St Andrew and Trowse, sparking concerns about the security of such sites.

The most recent incident saw the roof of a former Victorian pumping station in Trowse almost completely gutted as dozens of firefighters battled the overnight blaze. 

Norwich Evening News: There were fires across Norwich, including Thorpe St Andrew Hospital and Trowse Pumping Station, picturedThere were fires across Norwich, including Thorpe St Andrew Hospital and Trowse Pumping Station, pictured (Image: Christopher Tubby)

Norwich Evening News: The teenager arrested on suspicion of arson attacks across Norwich has been released under investigationThe teenager arrested on suspicion of arson attacks across Norwich has been released under investigation (Image: Newsquest)

Despite being arrested just four days after the pumping station fire, on November 16, police have released the unnamed teenager.

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He had previously been re-bailed on four separate occasions - the most recent until April 27 - with his bail conditions including an order to not enter derelict buildings and a curfew to stay home between 9pm and 6am.

Norwich Evening News: 42 firefighters were needed at the former St Andrews Hospital in October 202342 firefighters were needed at the former St Andrews Hospital in October 2023 (Image: Norfolk Constabulary)

Norwich Evening News: The aftermath of the Thorpe St Andrew Hospital fireThe aftermath of the Thorpe St Andrew Hospital fire (Image: Shaun Button, Drone Vision Norfolk)

Now police have confirmed he has been "released under investigation until July 1, 2024" meaning his restrictions have also been lifted.

No one was hurt in the fires but more than 40 firefighters were required to extinguish the blaze at the former St Andrews Hospital in Thorpe last October.

Norwich Evening News: The fire on the former May Gurney site in July 2023The fire on the former May Gurney site in July 2023 (Image: James Rose)Norwich Evening News: The building damaged in the fire at the May Gurney site in TrowseThe building damaged in the fire at the May Gurney site in Trowse (Image: Supplied)