A military base rocked by the death of six soldiers in Iraq is today marking its 200th anniversary.

Veterans from across Sussex will be attending a freedom parade honouring the Royal Military Police's Roussillon Barracks, which suffered its blackest day in the regiment's history when a group of its Red Caps were killed during a fierce firefight.

The barracks in Chichester, where the Red Caps trained, decided to go ahead with its celebrations but these are now likely to have an under-tone of remembrance in honour of the six men.

Servicemen and women from all over Britain will be attending the parade through the city which will be followed by a thanksgiving service in Chichester Cathedral.

Soldiers will be joined by 100 veterans and members of affiliated associations, including Chelsea Pensioners, for the service, which is being taken by the Dean, the Very Reverend Nicholas Frayling.

Many Sussex military personnel have laid floral tributes at the barracks.

Others have flocked to sign a book of condolence opened at the base where the regiment's blue and red flag, bearing the Royal Military Police coat of arms, has been flying at half-mast.

Among VIPs attending today's ceremony will be Hugh Wyatt, the Lord Lieutenant of West Sussex, the Duke of Richmond and Gordon and Chichester MP Andrew Tyrie.

After the service there will be a lunch at the barracks, followed by a party for people living near the headquarters in the evening.

Spokesman Captain Phil Packer said: "We are sharing our anniversary with the whole community. Although it is a thanksgiving service, we will be reflecting on what has happened this week."

The six men, who trained at the barracks, were Sergeant Simon Alexander Hamilton-Jewell, 41, from Chessington, Surrey, Corporal Russell Aston, 30, from Swadlincote, Derbyshire, Corporal Paul Graham Long, 24, from Colchester, Corporal Simon Miller, 21, from Tyne and Wear, Lance Corporal Benjamin John McGowan Hyde, 23, from Northallerton, North Yorkshire and Lance Corporal Thomas Richard Keys, 20, from Llanuwchllyn, near Bala, north Wales.

They died in a clash with a mob of locals in the Iraqi town of Majar Al-Kabir, near Amara, on Tuesday.