The incident took place during the district tournament at The Sele School in Hertford on Monday afternoon.

The boy was taken to Addenbrooke's Hospital in Cambridge in a critical condition, according to the East of England Ambulance Service.

Police later said the boy was in a "serious but stable condition".

The man was taken to Princess Alexandra Hospital in Harlow for further care.

The East of England Ambulance Service said: "We sent East Anglian Air Ambulance, two ambulance officer vehicles, an ambulance, a BASICS vehicle and a rapid response car.

"The child was taken to Addenbrooke's Hospital in a critical condition and the man was taken to Princess Alexandra Hospital for further care. Both were conveyed by land ambulance."

The service also thanked emergency service colleagues and members of the public at the scene who provided first aid and CPR before paramedics arrived.

Hertfordshire Constabulary said in a later statement: "Police were called at around 5.20pm on Monday to assist the ambulance service after two people were reported to have been hit by lightning.

"A boy and a man were attended to by paramedics and taken to hospital. He is currently in a serious but stable condition."

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The school's headteacher said the child involved in the incident was from another local school.

In a post on Facebook on Monday, he wrote: "Unfortunately, during the tournament, there was a lightning strike which affected several people, two of whom, one adult and one student from another local secondary school, were taken to hospital for treatment.

"The entire staff of The Sele School, the wider school community and I would like to thank the emergency services, the parents and staff who were attending the match and were so helpful and our first aiders who did an amazing job while waiting for the emergency services to respond.

"Our good wishes and thoughts are with the people who were injured."