The Wicker Man at Kettering's Wicksteed Park has been set on fire in what is believed to be an arson attack.
A force spokesman said the fire service were called at about 5.30pm yesterday (Monday) to the park after reports their 30ft wicker man was on fire.
Firefighters believed it to be arson and an investigation is now under way. The spokesman said offenders got in through fencing.
The minotaur has been completely burnt out, with just a part of his right arm and leg remaining on the wire frame.
It had been built earlier this year in preparation for Wicksteed Park's Bonfire Night on Saturday (November 2).
Every year, Wicksteed Park burns a wicker man alongside their fireworks display. This year is the park's 18th bonfire night event.
The minotaur was due to be lit at 7.15pm on the evening with fireworks following at around 8pm.
Those looking forward to the event have reacted angrily on Facebook after photos of the burnt minotaur were shared online.
Kate Mulliner took photos of the burnt minotaur this morning and said: "Gutted to see this on my walk this morning."
Many people have shared and commented on Kate's post expressing their disappointment and anger.
Police are asking anyone with information to call them on 101 quoting incident number 19000577398.
Wicksteed Park have been contacted for comment.
Wicksteed Park's Bonfire Night starts at 5pm and tickets can be bought online or on the gate.