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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Dry with warm sunny spells for most after a cloudy start in some areas
Two men have been stabbed in attacks in Luton town centre. Police have closed off two roads while they investigate the crimes.
It may start cloudy near coasts but the sun should break through, especially in the West.