An empty house in the Vale has had its windows smashed, rooms damaged and been covered in graffiti.
Guernsey Police say some witnesses have come forward seeing groups of young people at the property on Route des Coutures around the time.
Officers say it happened between Wednesday 13th and Saturday 23rd April, and forensic evidence has been found at the scene.
DS Telford says they believe one of the vandals cut themselves while they were in the house as bloody plasters and tissues were left at the house:
"Following the report, a Scenes of Crime officer attended the property and several items of important forensic value have been recovered.
We believe someone has cut themselves while within the house as there is evidence of bloodied plasters and tissues"
Anyone with information about the damage is asked to contact Guernsey Police on 222222 or contact Crimestoppers anonymously.

Prime Guernsey seafront location for sale
Woman (20) arrested on suspicion of attempted murder in Guernsey
Last day to register for Guernsey's upcoming by election
New citizen science project observing Guernsey dragonflies and damselflies
Channel Islands music school to hit global stage with Dubai launch
67,000 sickness days across the States of Guernsey last year
The Channel Islands are officially in meteorological drought
Islanders asked for views on body image and masculinity