He was escorted from the building after his case was heard by management yesterday.

Willie Lawson, the Communication Workers’ Union representive for the DD and PH postcode areas, said the sorting office worker had been sacked following a serious allegation.

He will now appeal the sacking, but it could be two months before he gets a hearing date.

The union will meet with workers tomorrow to urge them to go back to work in the meantime.

“Staff at Dundee East have taken unofficial strike action after one of their colleagues was summarily dismissed,” said Mr Lawson.

“They think he has been unfairly treated. I can’t go into the details of the case as it’s going through the appeal process.

“It’s a serious charge, but it’s not one I’ve ever heard before. I can say that it’s not a fraud or theft charge.

“Everyone has been fully supportive of the strike action today.

“We are now looking to get a date for an appeal hearing as soon as possible.

“That can normally take seven to eight weeks but we’re trying to push that as early as possible.

“There will be a meeting with staff at 5.30am tomorrow. Hopefully we can get them back to work.”

A Royal Mail spokesperson said, “Unfortunately 125 staff at Dundee East delivery office have taken unofficial strike action.

“This will have an impact on mail deliveries in the DD4 and DD5 postcode areas.

“Royal Mail apologies to our customers for this inconvenience and we urge our people to get back to work as soon as possible.

“We are aiming to deliver special delivery items in these area.

“Any customer awaiting a special delivery item and is concerned can also pick these items up at the Delivery Office in Ivory Place.”

The wildcat strike in Dundee comes as workers walked out in Edinburgh today as part of a campaign centred on claims Royal Mail is cutting pay and jobs of postal workers without agreement.