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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For some parts of the region, there's a risk of thunderstorms tonight before a mainly fine weekend.
Suffolk fire crews and care home managers have been practicing a major fire at a nursing home near Bury St Edmunds.
Last minute preparations are going on at the church where Princess Charlotte is to be christened on Sunday