A soldier has died during a training exercise in the Brecon Beacons in Wales, the Ministry of Defence said.
The senior NCO collapsed during a training exercise on Tuesday, which was the hottest day of the year so far.
The soldier is understood to be from the Rifles regiment and got into serious difficulties at around 9am when temperatures had already begun to rise above 25C.
The man, who has not been named by the MoD, was taking part in a seven-week promotion course to become a platoon sergeant.
An Army spokesperson said: “We can confirm that a soldier from ITC Catterick died on 19 July while conducting pre-course training for the Platoon Sergeants' Battle Course in Brecon.”
The Army describes the course as "one of the toughest training courses the Army offers".
The death comes three years after three young soldiers undergoing the SAS selection process died on the Brecon Beacons during one of the hottest days of 2013 when temperatures reached 27C.
The three soldiers’ deaths were due to a catalogue of “serious mistakes and systemic failures”, an inquest into the deaths ruled.
