A PAINTING of national importance - worth thousands of pounds - has been damaged in an accident at the National Railway Museum.

Embarrassed organisers were setting up for an evening event in the York museum's Station Hall when it is understood something ripped through the painting, Terence Cuneo’s famous depiction of Waterloo Station.

The painting, measuring 20ft by 10ft, is the largest one ever done by the renowned railway artist. Listed as part of the National Collection, it is described as “ incredibly important”.

It depicts the busy concourse of the London station and was commissioned by the Science Museum in 1967, where it was displayed for nearly 30 years before going to the National Railway Museum in York in 2007 for an exhibition marking the centenary of Cuneo’s birth.

A spokesman for the National Railway Museum said: "We can confirm there was an incident on the evening of Saturday June 28 involving Terence Cuneo’s Waterloo currently on display in Station Hall.

“ We are investigating the circumstances surrounding this accidental damage, which occurred during the set up for an evening event and have protected the painting while we assess the impact on this important artefact in the National Collection.”

The museum has called in conservators to see how bad the damage is, but it’s understood to be a rip in the canvas.

Waterloo Station is one of Terence Cuneo’s best known works, he was a particularly renowned artist after the war and was appointed as the official artist for the Queen’s coronation.

A bronze statue of him was erected at Waterloo Station in 2007. The painting features the artist himself, his wife and daughter, his assistant, various staff of the Science Museum, and even a couple of politicians including Harold Wilson being barked at by a bulldog.

A particular feature of many of his paintings, including Waterloo Station, was the inclusion of a tiny mouse and this became his trademark after 1956. They can be difficult to detect, in the Waterloo painting it’s perched on top of an advert for Johnnie Walker whisky.

Carole Cuneo, who helped set up the Terence Cuneo Memorial Trust following her father’s death in 1996 said it was upsetting that the painting had been damaged, but she was happy with the situation after staff at the museum confirmed that the damage was accidental and not vandalism.

The UK’s National Collection has nearly 200,000 paintings, including some of the greatest painters of the last 700 years, giving an insight into the history, landscape and culture of Britain.