British Army vehicles 'poisoning' troops with toxic carbon monoxide fumes

But the new report has lead to fears that a fix for the tank, which had its deployment halted in November 2025 after multiple soldiers fell ill while operating it, will require millions of pounds more of public funding.

The report concluded there was no single cause of the problems last year and are facing a "multi-factor combination" of problems, including mechanical defects, "faulty headsets", and possible missing air filters and leaks.

These leaks could allow carbon monoxide and carbon dioxide fumes into the vehicle, the potential cause of 33 soldiers falling ill with nausea, vomiting, numbness, hearing loss, muscle pain and pins and needles during a military exercises.

The leaked details from the official safety investigation also revealed problems with vehicles track, loose or missing "engine deck bolts" and unreliable power units.

The report, seen by the Mail, reads: "Their combined effect is assessed as capable of increasing exposure to noise, vibration, heat, fumes and workload."

Noise injury symptoms also had "likely contributors" in faulty headsets and "configuration errors".

The British Army is set to receive 589 Ajax vehicles, with the earliest delivery originally scheduled for 2017 and latest this year.

But the project failed to meet those deadlines, with the 40-ton vehicles being described as "a ridiculous project" by former Defence Secretary Sir Ben Wallace.

Colonel Hamish de Bretton-Gordon, former tank regiment commander, said: "If they have identified that filters are faulty or missing, that is a serious problem.

"But actually it's a very easy problem to fix - you just put new filters in them"

The inspectors did find the Ajax vehicle not to be unsafe when maintained and operated correctly, but also warned the "interaction of multiple factors may create conditions in which personnel experience symptoms of ill health".

The MoD was set to update MPs on the status of the project last Thursday, but it was announced it was delayed until early this week amid fears of finding several more millions in funding to fix problems with the vehicle.

Sources have suggested to the Mail the Ajax project will not be axed.

Lieutenant General Anna-Lee Reilly, addressing the Public Accounts Committee in March, said it was not "willful ignorance" that caused problems, but rather "part of operating on armour".

She added: "We know now, because we've done all of the research, that within that, if it is operated within those standards and within those specifications, it is safe – that's what we are being told by the Army safety investigation team, that's what's been reported."

Ajax is described by the British Army as the "most advanced, medium weight, armoured fighting vehicle in the world".

It has six intended variants, with functions ranging from equipment support with tow lines and cranes to all-weather specialist support designs.

The MoD said: "The safety of our people is non-negotiable. An extensive safety investigation into Exercise Titan Storm has now concluded, with an update to Parliament expected in the coming days."