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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Rain easing for a time, but heavy showers possible later.
22 Albatross boats, glamorised by the likes of Brigit Bardot and Prince Rainier, are sailing in Norfolk and Suffolk this weekend.
Risk of heavy rain overnight and later Sunday.