Paul Remington vice chair of the East of England Ambulance trust thanks Ms Ball for her hard work.
He said: “Maria spent many years leading the ambulance service and I would like to thank her for her dedication and commitment through what have been some challenging times.
"Maria oversaw the formation of this Trust, bringing together three disparate organisations into one service, and its subsequent development."
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Showers dying out during this evening to leave a dry night with some long clear spells leading to a frost by morning. Lows -1 deg C
A protest march has been held in Huntingdon over plans to merge two local hospitals to save money.
A protest march has taken place in Huntingdon over plans which could see Hinchingbrooke Hospital merge with Peterborough City Hospital