Craig Roberts, Edward Maher and James Dunsby died in the UK armed forces in 2013. Not in war zones, but in training.

The young soldiers were taking part in an elite selection test in the Brecon Beacons for the British Army's SAS reserves when they collapsed in the heat.

In 2015, the Ministry of Defence (MoD) admitted mistakes were made and insisted lessons had been learned.

A year later, it happened again. This time, Corporal Joshua Hoole passed away during a fitness test.

He is now one of 148 people who have died in military training in the past 20 years.

BBC Wales Investigates has also learnt that the Army has breached health and safety law 40 times.

The MoD insists it has taken action to prevent casualties.

Experts and families are warning lives are still at risk.

See the full programme on BBC One Wales at 20:00 GMT on Wednesday, 19 February and then on the BBC iPlayer.

Reporters: Liz Clements and Wyre Davies

Produced by: Paul Heaney and Clare Hutchinson

Filmed by: Jon Rees

Additional filming: Paul Heaney, Clare Hutchinson and Richard Longstaff

Editor: Philip John

Commissioning Editor: Kimberley Rowell