POLICE have appealed for people to come forward and help them catch thieves who staggered out of a school yard with 45 historic stone flags.

All Saints Primary School, in Clayton-le-Moors, lost the flags after eight men were spotted by neighbours using crow bars to lift them up from the ground.

Headmaster Peter Jump said the stones were "irreplaceable" and dated back to the 1840s when the old school building was built. He has had to sell the remaining flags on the advice of police who feared the thieves might return for the ones they left.

Community Beat Officer Tracy Finn said police had devised an ultraviolet marking scheme to tackle the problem, but they need more people to come forward and pick up the pens to make it a success.

The theft at All Saints is one of a growing number of incidents to hit Hyndburn and areas of Burnley and the Ribble Valley.

Mr Jump said: "The flags were the original 1840 flag stones, they were irreplaceable and an historic feature of the school.

"They were part of the old school building, now the kitchen, and formed the old entrance to the school. We've heard a number of estimates from £400 from the police, or £80 a flag to £35 a tonne. They stole about four tonnes.

"There was no way we could replace them, the best way was to get some money for them for the job of asphalting the area as the police said the thieves would be back to steal the others they left.

PCSO Tracy Finn said: "We have a marking scheme underway whereby residents, businesses and farmers can pick up an ultraviolet marker pen and mark their stones as they would their cycles or videos.

"They may seem like just stones but they fetch a lot of money for thieves and if they are not marked we won't ever have the chance of tracing them.

"We want everybody to come to us either phone us on 01254 353103 or go to your local police station, we need people to come forward to stop these thieves."

Sgt Claire Holbrook said: "We also need people to keep an eye out and watch for suspicious behaviour, because we also need to catch these criminals in the act.

"We know they sometimes wear fluorescent jackets so they seem official so we need people to be more aware."