Police are appealing for public assistance after an explosion caused significant damage to a surf club in the Lake Macquarie region.
About 10pm today, there was an explosion in the public toilets of the Redhead Beach Surf Club.
The blast caused serious damage to the ceiling and roof of the premises and also caused a window to blow out, NSW Police say.
Police attended and established a crime scene which was examined by forensic specialists.
Officers from Lake Macquarie Local Area Command are conducting inquiries.
Police are treating this as a hoodlum incident.
Anyone with information is urged to contact Crime Stopers.