The London Ambulance Service had its busiest day in history on Friday as scorching temperatures soared across the capital amid a record-breaking June heatwave.

The service received 8,869 emergency calls and responded to 688 life-threatening incidents, including people in cardiac arrest or who have stopped breathing.

Between 6pm and midnight they answered more than 500 calls an hour. 

Friday was the hottest June day on record, which reached a blistering 37.3C in Suffolk, the Met Office said.

The emergency service wrote on Saturday on X: 'Yesterday was our busiest day in history. Thank you to all our crews and call handlers. 

'Please only use 999 in a life-threatening emergency.'

London Ambulance Service said demand for the service was so high on Friday that they declared a critical incident between 10pm and 1.30am.   

The demand was higher than during May's heatwave and the peak of the COVID-19 pandemic. 

On Wednesday, temperatures soared to 36.1C in Charlwood, Surrey and ambulance crews responded to a record 642 Category 1 calls.

Friday's temperatures smashed the long-standing June record of 35.6C, set in the summer of 1976, by more than 1C – a significant margin given such records have historically been broken only by fractions of a degree. 

An amber warning of extreme heat remains in place from midnight until 9pm on Saturday across the south east of England and East Anglia. 

The London Ambulance Service urged people to stay safe tonight as England will be playing in the world cup and temperatures are expected to remain high.

Lower temperatures are expected to develop in the west this weekend, with these fresher conditions spreading slowly further east.

Craig Harman, Chief Operating Officer at London Ambulance Service, said: 'I couldn't be prouder of our staff and volunteers, who have worked tirelessly through the hottest days of the year and the busiest period in our history to continue to provide Londoners with care and compassion.

'Despite bringing in more than 400 additional ambulance crews and increasing staffing across our 999 and 111 control rooms, demand has remained exceptionally high this week.

'We have now stood down the critical incident but remain very busy. If you're enjoying the sunshine or cheering on England this evening, please stay hydrated, drink responsibly and look after each other.'