Almost 700 British servicemen and women have returned from Iraq with mental health problems including post-traumatic stress disorder.

The latest figures seen by The Independent show that 19 service personnel have had to be discharged because of psychiatric problems.

Between the beginning of the conflict in March 2003 and September 2004, 687 serving military personnel, predominantly soldiers, were treated. Of these, 77 were diagnosed with post-traumatic stress disorder and 382 with adjustment disorder or combat stress. A further 228 were treated for a range of problems such as depression, neurosis or misuse of medication. These figures are expected to rise when the Ministry of Defence releases data for the last three months of 2004.

The latest information suggests that more than 1 per cent of the 65,000 soldiers, sailors and airmen who have served in the conflict are suffering from related mental health problems. Experts estimate that the figure could be double, because of those who would not or had yet to seek help.

A defence spokesman said that the adjustment disorder figure included personnel with problems not directly related to combat, such as relationship difficulties due to deployment.

To spot symptoms of mental health problems among service personnel early, psychiatrists are deployed to combat zones, commanders are briefed to look out for changes in behaviour, and personnel are asked to complete mental health questionnaires upon their return.