A garden deck at the back of a house in Crick was set on fire by vandals.
The incident happened in Chapel Lane sometime between 11.30pm on Friday, June 26, and 1.30am the following morning. Nobody was injured.
Witnesses, or anyone who knows anything about this incident, can call Northamptonshire Police on 101.
Alternatively, they can call the independent charity Crimestoppers anonymously on 0800 555 111 or use the anonymous online form at www.crimestoppers-uk.org.