Passengers travelling on London's new Routemaster buses have been suffering in the heat as a technical fault has made the Boris buses like "moving saunas".
The Evening Standard reports that heat levels on the buses' upper decks were recorded at more than 30C yesterday, which is the maximum for transporting farm animals across Europe.
Transport for London admitted "teething problems" and encouraged passengers to make a complaint.
Many took to Twitter to report the uncomfortable conditions.
One branded the buses as "hotter than magma", while another dubbed them "moving saunas".
Another passenger tweeted: "Never get on the 24 bus unless you want to faint, we were all slabs of crispy bacon dripping with oil about to be eaten".
A TfL spokeswoman said: "We would ask any passenger who feels our service falls below what they expect – for example the air cooling system on the bus not working – to contact us on 0845 300 7000 or email email@example.com Their concerns will be fully investigated."
The BBC reports that Mike Western, operations director for London Buses, said the "technical issues" were being resolved.
"Our suppliers are working to fix the issue as soon as possible," he said.
"When the air chill system is fully operational we are finding temperature levels are comparable to other buses in our fleet fitted with a similar system.
"As you would expect with the introduction of a large fleet of new buses, there will be teething problems and we are working hard to minimise the impact of these on our passengers."
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