William, 33, was among a team that also included a co-pilot, a doctor and a paramedic who were called to the scene when the girl – who was a pedestrian – was hurt following a crash between a blue Mercedes and a silver Ford KA on Old Road in Leighton Buzzard, about 45 miles north of London. Authorities are appealing for witnesses.
“She had life-threatening injuries, including a broken pelvis and suspected broken legs,” an ambulance spokeswoman tells PEOPLE.
The girl, who was flown by William to a hospital in Cambridge, 50 miles north, remains in a serious condition, according to Bedfordshire police.
A second girl, who was also involved in the collision sustained only minor injuries, officials say.
He has been actively involved from the start, and has even touched down at a prison for one dramatic mission.
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