Britain is braced for an outbreak of wildfires as the country continues to swelter in its longest heatwave for seven years.
Researchers have estimated that the hot weather may have caused up to 760 premature deaths after six consecutive days of plus-30C temperatures. And with rainfall at only around 15% of average monthly totals so far, the Met Office has warned that there is an "elevated risk" of fires in the countryside.
A spokesman said: "I can confirm that the advice given to our governmental partners is that there is an elevated risk of fires in the next couple of days."
Karl Kitchen, the Met Office scientist with responsibility for wildfires, told The Independent that soon-to-be harvested crops such as wheat and winter barley are looking particularly vulnerable to fire.
Firefighters in London have already warned of the dangers posed by grass fires.
Yesterday, a blaze burned through grass and gorse the equivalent of four football pitches in Mitcham, south London, before it was brought under control.
London Fire Brigade (LFB) says it has dealt with twice as many grass fires in this summer's heatwave compared with last year.
The country experienced the hottest day of the year so far on Wednesday, with the mercury hitting 32.2C (90F).
South-west England and the West Midlands were elevated from level two to level three heatwave health warnings by the Met Office yesterday, putting them on a par with the South East and London.
The East Midlands, Yorkshire and the Humber, and the East remain at level two. The North East and North West remain at level one.
Health officials have advised people to stay cool, drink lots of cold fluids and keep an eye on those they know to be at risk.
Dr Angie Bone, heatwave plan leader for PHE, said: "In this continued hot weather, it's important to remember that high temperatures can be dangerous, especially for people who may be vulnerable such as older people, young children and those with serious illnesses.
"During very hot weather, pregnant women and people who have chronic illnesses, including cardiovascular, respiratory, renal conditions, diabetes or Parkinson's disease, may experience discomfort if indoor temperatures are particularly hot and in using public transport."
Gemma Plumb, a forecaster with MeteoGroup, the weather division of the Press Association, said there was no sign of temperatures dropping significantly in the coming days.
"The West Midlands, central southern England and the West Country could see maximums of 28-30C," she said.
"On Saturday and Sunday it looks like we will have temperatures of around 28C but by Monday we have temperatures of 29C and 30C again, with an increased risk of getting some showers.
"There is a likelihood of thunderstorms from Sunday and into Monday, initially in the west of England and South Wales and then heading into the south of England, but these would not necessarily bring temperatures down."
A four-week-old baby was among 10 children admitted to one hospital in the South East with sunburn since the period of hot weather began.
The oldest patient was 14, according to the Queen Victoria Hospital in East Grinstead, West Sussex.
Six of the 10 children admitted needed specialist treatment after being referred to the unit from other hospitals because of the severity of their burns.
A spokesman for the hospital said the extent of the burns ranged from 0.5% to 4% of the body surface area. All the children came from the South East, from Chichester in West Sussex to Swanley in Kent.
Consultant plastic surgeon Nora Nugent said: "The sun at this time of year is very strong and children can get burnt very quickly.
"The children we've treated over the last few weeks have been referred to our unit because their burns have been so severe they have required specialist treatment."
In Wales, doctors at the Abertawe Bro Morgannwg University Health Board warned of the dangers of ride-on lawn mowers after seeing plastic surgery trauma cases double to 53.
Dean Boyce, consultant plastic surgeon at the Welsh Centre for Burns and Plastic Surgery at Morriston Hospital in Swansea, said: "Unfortunately we are treating a patient with a very severe foot injury, and this is not the first time this has happened.
"We have seen children who have lost a foot after falling off a parent's lap riding a ride-on mower.
"We would warn people to avoid letting anyone ride on their lap for fun because in fact this is very dangerous, as the mower's safety cut out will not engage if they fall off."
Reports of dogs being left in cars with windows closed in the sweltering conditions have also prompted warnings from the police.
Leaving a window open is not enough to prevent a dog from dying in the heat, police warned.
Police and fire chiefs have also reiterated warnings about escaping the heat by swimming in open water after a number of deaths in recent weeks.
Four people died in separate incidents on Tuesday in lakes, rivers and the sea in Norfolk, the Shropshire-north Wales border and Cornwall.