The Trust has released a statement saying Maria Ball has resigned with immediate effect.
The process for appointing a new or interim chair will be started immediately but in the meantime Paul Remington who is vice chair will lead the organisation with Andrew Morgan, the interim chief executive.
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A change in wind direction brings warmer temperatures to the Anglia region
The RSPCA is investigating after two thin dogs were found abandoned, in a neglected state, on an isolated road in Hertfordshire.
Warm sunny spells today remaining dry