The Imperial War Museum has catalogued 27,000 war memorials across the UK, although it is believed the total, including those yet to be identified, could be around 60,000. Most were erected after the First World War, which ended 80 years ago this year, and there are more than 1,000 recalling the Boer War.
Three years ago the Friends of War Memorials was founded to clean up and repair the memorials, but despite its efforts, including the recruitment of convicted juvenile offenders, the relentless vandalism continues.
Some have been daubed with graffiti, bayonets of soldiers cast in bronze have been snapped off, and other monuments have been taken and melted down. Monuments and plaques bearing the names of war dead have been discovered in skips and scrapyards. Thieves also prize them as items to be sold as garden sculpture
"War memorials are being damaged and stolen left, right and centre. So many have just disappeared," said Ian Davidson, an ex-marine and founder of Friends of War Memorials. "The bronze and brass of the plaques are immaterial. It's the names we are concerned about. These people gave their lives."
They include plaques and memorials in police stations, churches and factories, which were forgotten when the buildings closed. Hundreds of plaques disappeared during railway-line closures in the Sixties, Mr Davidson said.
The group has rescued several memorials which are kept at the Royal Hospital, Chelsea, home to many veterans. And the Friends' catalogue of cases illustrates the neglect.
This year youths defaced a war memorial in Tullibody, near Stirling, although their parents cleaned up the damage. The Heroes' Shrine at Aldershot, heartland of the British Army, is less than a mile from part of the main garrison. Yet the monument two years ago was "disgustingly vandalised and allowed to run down", Mr Davidson said.
In other attacks, the head was smashed from a statue in Richmond, and a copper scroll was stolen from a memorial in Hucknall, Nottinghamshire.
The group has worked with probation authorities in 11 counties, encouraging the use of community-service orders to clean up monuments. In Yorkshire, the Royal British Legion co-ordinates the work.
The way changed circumstances can jeopardise a war memorial was highlighted in 1995, when the Japanese owners of County Hal, in London banned veterans from the building's war memorial. The company only backed down after intervention from the Japanese Embassy and the Royal British Legion.