Services through the Channel Tunnel using one of the two running tunnels, were able to continue but Eurotunnel warned that services were being delayed, with hold-ups possibly lasting for the rest of the day.
The evacuated passengers are now at the French terminal and are waiting for the affected train to arrive so they can get their cars
We are advising people who don't need to travel today to travel on another day. There are queues building up and travellers should expect delays throughout the day.
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The high of 35C was recorded on a Bakerloo line train between Piccadilly Circus and Oxford Circus at 2pm.
Weather forecasters say temperatures could reach 35C, beating the previous record of 34.6C in the scorching summer of 1976.
After years of political manoeuvring over the future expansion of Heathrow Airport, there has been an important development this lunchtime.