A £500 reward has been offered to help catch thieves who smashed their way in to York Theatre Royal and stole more than £1,000 in donations towards its redevelopment appeal.

Cleaners arrived to work at 7am yesterday to discover a pane of glass in the 1967 foyer extension had been smashed with part of a paving slab overnight.

The intruders then used another paving slab to smash into the theatre’s donations box, believed to have had in excess of £1,000 in it, said a spokeswoman.

"During the run of the pantomime, Old Mother Goose, the theatre has been asking audiences to contribute to the capital building appeal," she said.

"After every performance, Berwick Kaler makes an announcement from the stage asking audiences to dig deep and leave a few pounds in buckets as they leave the theatre.

"In addition, the theatre fixed a donations box to the foyer wall, not visible from the street, and it is this box that has been subject to theft."

A businesswoman who read about the theft on The Press website yesterday was prompted to offer a £500 reward for anyone providing information leading to the arrest and conviction of those responsible.

Chelle Thirsk, a director of CGA, of Riccall Road, Escrick, said she regularly visited the theatre and panto and donated both times during visits last month, and she was 'disgusted' by the theft.

She said that if no one was arrested, she would instead donate the money to the theatre’s appeal.

Theatre chief executive Liz Wilson said that what made her so sad about the theft was that audiences over the festive season had given the money to help support the theatre, which was in the process of raising the last £500,000 needed to transform the foyer space, café, toilets, disability access, auditorium and stage.

"Families over Christmas have donated money and we even know of children who have enjoyed putting their pocket money in the box," she said.

"It is a huge blow for the theatre, with just weeks to go until it closes for a major re-development that will cost £4.1 million.

North Yorkshire Police said officers were investigating the break-in and anyone with information should call 101, quoting crime ref number 42/23/2015.