Vandals torched a school building then flooded classrooms by setting off a hosepipe.

They then left the device on causing almost £5,000 of damage and major setbacks to the building of an extension at Church St Nicholas CE Primary.

Headteacher Jacqueline Gilbert said the mindless attack has left schoolchildren, parents and staff completely ‘bewildered.’

She said a portable cabin was set on fire by arsonists, a store room was flooded and classrooms damaged during the incident.

“All of us at the school were heartbroken when we saw what had been done,” said Mrs Gilbert.

“The floor of one of the new classrooms has been ruined by water, and the contractors’ cabin has been destroyed by fire.

“It’s unthinkable that there are people out there who would want to do this to a primary school, of all places.”

The voluntary-aided school is governed by the Diocese which has funded the £250,000 building project that began in December last year and is due for completion in May.

The building work will extend all junior classrooms at the Dill Hall Lane-based school so they can make better use of space in an open-plan design.

But a new portable cabin will now have to be purchased and the damaged classroom floors repaired.

An arson investigation is underway after police and fire attended the scene following the events on midnight on Saturday, April 2. 

Mrs Gilbert said: “These youths have broken into a secure site.

“They have walked all over one of the new floors, then found a hosepipe and deliberately set it up and left it running.

“The children are scared to leave anything out now. It's difficult for them to understand why people would do this.

“In this day and age this amount of money lost on this could be the difference between our children having music lessons or not.”

Sgt Simon Holderness, of Accrington Police, said an investigation was now underway.

He said: “We have started an investigation. A fire report from Lancashire Fire and Rescue Service concluded that youths started the fire.

“The offenders put a small amount of wood and a tyre next to the cabin and set it on fire, causing damage to its side and interior.” Mrs Gilbert added: “The children are just bewildered - they were really looking forward to their new rooms and they can’t understand why this has happened.”