The British death toll in Iraq would be almost one-third higher if Ministry of Defence figures included former UK soldiers on government contracts, The Herald can reveal.

While 133 British soldiers and airmen have died as the result of hostile action since 2003, at least 44 British private security employees have also been killed.

They are mostly former special forces soldiers or paratroopers who left the Army to earn up to £7000 a month tax-free, six or seven times their service take-home pay.

The MoD does not record contractor casualties, though those on US government contracts have their nationalities logged by the American Department of Labour.

More than 1000 contractors have been killed, including three Scots and almost 200 "shooters" employed as close-protection bodyguards or convoy escorts. A further 12,000 hired guns, drivers and technicians have been wounded.

The estimated 21,000 British mercenaries operating in Iraq outnumber British service personnel by four to one. About 48,000 international soldiers of fortune work for private companies.

Andrew Whyte, 50, a Dundonian former soldier, was killed in an ambush near Beiji in 2005; Scott Mounce, 30, a computer expert from Inverness died in a car bomb attack; and Darren Bull, 34, a former Scots Guardsman, was shot dead outside Falluja in October last year.