Lifeboat officials in Northumberland have condemned vandals who damaged a lighthouse and prompted a rescue alert.
The Blyth lifeboat was scrambled on Sunday, after reports up to 30 youths were stranded on the town's east pier.
When crews arrived at the pier, they discovered the lighthouse had been broken into and windows smashed.
A spokesman for the Royal National Lifeboat Institution (RNLI) said the incident could have created a hazard to approaching vessels.
An RNLI spokesman said: "That the young persons had put themselves and others in danger by going onto the East Pier and the damage to the lighthouse, could have created a navigational hazard."
Police are investigating the incident.