Jim Reeves, from the Communication Workers' Union, says the argument to close 70 Crown Post Offices is flawed because the business is profitable.
He spoke to ITV News Central outside the Kings Heath branch in Birmingham as staff went of strike this morning.
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A man was stabbed in the leg during a large altercation in a pub.
Thick cloud with outbursts of rain will spread east as the night goes on.
Heavy bursts of rain will develop overnight, with some fog and mist.