Vandals have desecrated an ANZAC war cemetery in Harefield ahead of this weekend's Gallipoli centenary commemorations.

They sawed an Australian flagpole and peppered a memorial and information panel with blue paint at Harefield (St Mary's) Churchyard, in Church Hill, where the bodies of more than 100 Australian soldiers killed in the First World War are interred.

The burial site is due to host a special ANZAC (Australian and New Zealand Army Corps) Day service on Saturday (April 25) afternoon, marking the centenary of the start of the Gallipoli Campaign, in which more than 11,000 soldiers from Australia and New Zealand were killed

The Commonwealth War Graves Commission, which maintains the site, condemned the vandals but said the ceremony would go ahead as planned despite their actions.

"The vandalism is very upsetting for the Commission, after all the work (to restore the graves) that has taken place over the last three months," said a spokesman for the commission, which is working to repair the damage in time.

Blue paint on an information panel in the ANZAC cemetery at Harefield (St Mary's) Churchyard, which was desecrated by vandals

The cemetery is the UK's primary place of remembrance for Australian First World War casualties and has hosted an annual ANZAC Day service, at which local schoolchildren lay flowers on every grave, since 1921.

A new visitor information panel, allowing people to use their mobiles to reveal the personal stories of some of those buried there, was due to be unveiled following this year's ceremony.

But that was also vandalised and it is yet to be confirmed whether the unveiling will go ahead as planned on the day.

Harefield House and its grounds were used as a hospital for wounded Australian soldiers during the First World War, during which some 50,000 patients were treated there. Of those, 112 soldiers died and were buried in the parish graveyard along with a female nurse.

Francis Newdegate, a local MP who was later appointed governor of Tasmania, offered a plot of land beside the churchyard to extend the cemetery.

The Australian flag is raised at the ANZAC cemetery at Harefield (St Mary) Churchyard, before the flagpole was vandalised

He also covered the funeral expenses for all the burials, for which the village school lent its Union flag. After the war that flag was presented to the last CO of the Australian hospital and laid up in Adelaide High School.

In return, the Australian Children's Patriotic League presented a new Union Flag and an Australian flag to Harefield school. The Australian flag hangs in the Breakspear Chapel, which was rededicated as the Australian Chapel in 1951.

The ANZAC Day service is due to take place at St Mary's Parish Church at 3pm and is open to all. It will be followed by a wreath-laying ceremony in the ANZAC cemetery.