It's estimated that thousands of British troops will return from Afghanistan with post-traumatic stress disorder.
Grant Woodward reports on a hidden condition that's a potential killer
Simon Buckden left Bosnia fifteen years ago – but in his mind he's still there.
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The slightest thing can set him off, sending his thoughts tumbling back to the horrors he witnessed in the former Yugoslavia.
The 38-year-old is one of thousands of ex-servicemen and women
suffering from post-traumatic stress disorder – a psychological and physical condition that's caused by especially frightening or distressing events.
It first came to prominence during the First World War when soldiers suffered harrowing experiences in the trenches. Their condition became known as shell shock or battle fatigue syndrome.
It was only after the Vietnam War that the term post-traumatic stress disorder (PTSD) was first used to describe the fractured mental state of veterans.
Now it's feared that thousands of British soldiers returning from conflicts in Afghanistan and Iraq will find themselves suffering from its potentially deadly effects.
In Simon's case he has no doubt his trauma was triggered by the horrors he witnessed during two tours of Bosnia in the mid-1990s as war raged between the Croats and Serbs.
"I first went there in 1994 with the UN peacekeeping force, which meant we couldn't do anything," he recalls. "We just had to watch what was going on. That made it worse because you just felt utterly helpless."
The war was characterised by bitter fighting, indiscriminate shelling of cities and towns, ethnic cleansing, systematic mass rape and genocide.
Events such as those at the Omarska concentration camp, where hundreds died of starvation, punishment beatings and ill-treatment, and the Srebrenica massacre, which saw Bosnian Serbs slaughter more than 8,000 civilians and prisoners, mostly men and boys, would come to typify the conflict.
Serving with the Royal Signals, Simon's role was to work with journalists, who would be driven to the scenes of atrocities so they could report on them.
"The Serbs usually took anybody who was fit enough and put them to work in the fields," says Simon, of Bramley, Leeds.
"The rest – the elderly, along with women and children – were either forcibly displaced or shot.
"You would go into a town two or three days later and it would be razed to the ground.
"In the cellars you'd find the bodies of those they had tortured, raped and then killed before setting fire to them."
On another occasion he was driving an interpreter back to her village when it suddenly came under heavy shellfire from Serb forces.
He says he is still haunted by the memory of a fatally wounded child he tried to save.
"He was a boy of around six or seven who had lost an arm and both his legs," he recalls. "He bled to death in my arms."
After returning from the war zone, Simon says he was a changed man. He felt numb, cut off from family and friends and soon found himself drowning in a sea of booze.
Increasingly prone to angry outbursts, his marriage imploded and his 12-year Army career ended with a medical discharge on the grounds of recurrent depression – with no mention of PTSD.
Simon strongly believes the original omission – overturned in 2005 – was part of an attempt by the armed forces to play down the scale of the issue among ex-servicemen.
Back on Civvy Street, he initially did well in a new career in recruitment, but soon reached the point where he found himself unable to function.
"I just found myself shutting down." he says. "It felt like I was falling off a cliff.
"I was getting up ill every day and eventually my friends said that if I carried on I would end up killing myself."
Simon says he knows of 10 former Army colleagues who have committed suicide and admits he has harboured similarly dark thoughts.
"I still have suicidal thoughts," he says. "It's just another part of daily life. I don't tell people I want to die, but I know I don't want to carry on like this."
Combat Stress is the leading UK military charity and service provider in the care of veterans' mental health.
It offers free treatment for PTSD, along with depression, anxiety and
The organisation currently helps more than 4,400 ex-servicemen, including over a hundred who have served in Afghanistan and over 400 who fought in Iraq.
Last year alone, it received 1,303 new referrals – up 72 per cent since 2005.
Its youngest veteran is 20, the oldest 103. The vast majority served in the Army.
Now Combat Stress is warning Britain faces a ticking timebomb among troops who have served tours of duty in Afghanistan and Iraq.
A study this year showed four per cent of the estimated 180,000 troops who have served in those two operations will develop PTSD. That equates to 7,200 more sufferers.
The study also highlighted a prevalence for common mental disorders and alcohol misuse.
One of the biggest problems is that ex-servicemen are often too proud to ask for help.
"On average, it takes 14 years from service discharge for veterans to make the first-step approach to Combat Stress for help, by which time their condition is often highly complex," said a spokesman.
There's another price that comes with PTSD too.
In the last five years the number of ex-servicemen and women in UK prisons has reached an estimated 8,500 with another 3,000 on parole – at a cost to society of over 300m a year. Of these, it's estimated that one in two suffer from PTSD and related disorders.
Earlier this year Combat Stress signed a partnership agreement with the MoD and the Department of Health, resulting in an investment of 350,000.
This will help Combat Stress staff to work directly with NHS mental health Trusts to ensure that the services they provide are accessible to and appropriate for military veterans.
The organisation's patron the Prince of Wales has also launched a 30 million fundraising campaign – The Enemy Within Appeal.
This three-year appeal aims to help ex-servicemen rebuild their lives by establishing 14 Community Outreach Teams around the country made up of mental health practitioners, community psychiatric nurses and regional welfare officers
Funds will also be put toward enhancing clinical treatment at its three short-stay treatment centres in Ayrshire, Shropshire and Surrey.
Simon has had stints at two of the centres and is grateful for the assistance Combat Stress has provided him.
But he is still unable to work and in his lowest moments doubts if he will ever conquer PTSD and get his life back on track.
"I don't think I will get better, as far as I know there isn't a cure. I've tried medication but it just numbs you and I don't want to live like that.
"It's just a case of trying to manage the symptoms so you can have the best possible quality of life.
"But I'm probably one of the lucky ones," he says. "At least I had 12 years in the Army.
"It's the lads who are coming back from Afghanistan at the age of 18 or 19 I really feel for. They've got this for the rest of their lives."
* For more information on PTSD visit: www.combatstress.org.uk