A woman fainted and commuters complained of "sweltering" temperatures on board trains after a rail operator left the heating on for the hottest day of the year so far.
Passengers sweated through their journeys on commuter trains as London basked in 21C heat on Thursday - the hottest March day in the UK for five years.
Customers likened carriages on Southeastern Rail trains to a "sauna" and said the situation was made worse by "disgusting" overcrowding.
Alex Beckett, a food researcher from Charlton, said the unbearable temperatures caused a woman to faint as the train crawled at a “snail’s pace” past London Bridge.
He was travelling on the 8.08am commuter train to Cannon Street and told the Standard: “Just before we got to London Bridge the woman stood in front of me and collapsed onto me.
“I caught her and let her down gently on the ground. Everyone made space and began to fan her until she woke up.
“The train was so crowded and boiling. Everyone knew that it was going to be the hottest day of the year so why did they have the heating on?
Londoners bask in spring sunshine - March 30 2017
“And on that journey there are lots of mums on that train dropping their children off at nursery.”
Mr Beckett, 39, added: “They are putting up the prices of our tickets and surely a great way to save money and energy would be to turn it off.”
And frustrated commuters complained about the same problem on multiple other services operating throughout Thursday.
A Twitter user named Mase wrote: “@Se_Railway it's going to be 21 degrees today why is the heating still on, I can only assume that you have built trains in which you have no control over the heating? It's not cold outside!!!!!!!”
And another wrote: “@Se_Railway turn heating off!!!!! 7.13 Crayford to London Charing Cross!!! Is the driver mad??”
Later on in the evening, Neil Bartlett tweeted: “@Se_Railway Could you ask the drive to turn off the heating on the 19:09 from Charing Cross, please? It's sweltering on here.”
One commuter even said that the conditions had caused her to be physically sick.
Bernie Doyle tweeted: “Just got home and threw up thanks to the disgusting conditions on that train. Cheers Southeastern.”
Read More
When asked to send her contact details and an explanation as to what happened, she added: “Simple. There was no air con on a disgustingly overcrowded train.”
A Southeastern spokesperson said: "We’re sorry if some journeys were uncomfortable yesterday.
"The specific train in question is fitted with air conditioning, so it sounds like there may have been a fault with the system.
"Thanks to our passenger letting us know, we're looking into this right away with our engineering team to fix any problem."
MORE ABOUT