It is understood the former finance director and executive director of the authority, who commanded a salary in excess of £180,000, left by mutual agreement.
The full details of Mr Mason’s departure – and whether he received any financial compensation – have not been confirmed.
Mr Mason had come under fire for banning public notices in the Hexham Courant . He was accused of making the decision in ‘a fit of pique’ to punish the Courant over its coverage of objections to new charges in the county’s leisure centres.
And the polarised views of Mr Mason and the council’s new Conservative leader, Peter Jackson, on key issues such as the project to build a new County Hall in Ashington, were no secret.
The Conservatives reinstated the notices, following their landmark local election win two weeks ago.
And as councillors met on Wednesday for the first full council meeting in Morpeth since the local elections, Mr Mason’s chair remained empty.
Despite repeated requests for a comment, Mr Mason failed to respond this week.
This week, the authority's deputy chief executive, Daljit Lally, took the lead on issuing public statements and dealing with correspondence.
Mr Mason has failed to respond to requests for a comment.
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