A 33-year-old woman and a 38-year-old man have been arrested after a hot tub was set on fire.
The pair were arrested on suspicion of arson and have been released under investigation while enquiries continue in to the incident, which took place at around 4am on Saturday, November 18 in the garden of a house in Maple Drive, Belper.
Officers are keen for anybody who may have seen anyone in or around where the blaze took place to get in contact.
Witnesses or anyone with information can call DC Thor Long on 101 quoting reference 17000503003.
Alternatively, send him a message online by visiting the Contact Us section of the Derbyshire Constabulary website.
You can also call Crimestoppers on 0800 555 111.