Three troops faint in military parade inspected by Prince William amid record temperatures

Prince William acknowledged the 'difficult conditions'

Prince William, who inspected the Colonel's Review, acknowledged in a tweet that conditions were "difficult".

The Met Office confirmed shortly before 2pm Saturday that a high of 30.5C was recorded at Heathrow.

According to the Met Office, the 30-degree mark is the earliest reached in England in nearly two decades.

The Prince of Wales, who led the Colonel's Review at Horse Guards Parade in Central London, paid tribute to the soldiers who participated in the heat.

He tweeted: "A big thank you to every solider (sic) who took part in the Colonel's Review this morning in the heat. Difficult conditions but you all did a really good job. Thank you. W."

Photos taken at the parade show one soldier being taken away by stretcher. Another showed a soldier lying down at his comrades feet, instrument still in hand.

Sky News reported that more than 1,400 soldiers and 200 horses from the Household Division of Welsh, Irish, Scottish, Grenadier and Coldstream Guards paraded for inspection by Prince William during the rehearsal.

It was held ahead of next Saturday's Trooping the Colour parade.

Earlier this week, the Met Office issued its first heat-alert across much of England.

The UK Health Security Agency (UKHSA) issued an amber heat-health alert for hot weather until 9am on Tuesday in the West Midlands, East Midlands, East of England, South East and South West.

The alert means that the impact of the weather is "likely to be felt across the whole health service… and the wider population, not just the most vulnerable".

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