"We are low paid workers. We've had a pay freeze for two years" says Dave Warren, from the PCS union.
"This year, there's a one percent increase available, which is a joke in itself, but apparently the Government wants to tie that to the loss of our terms and conditions. We find that totally unacceptable."
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Two people have died after being involved in separate lightning strikes in Wales' Brecon Beacons today.
Any lingering showers will ease this evening, to leave a dry night with plenty of clear spells. Minimum temperature 11 deg C (52 deg F).
Blackwood mother Trudy Jones was on holiday when she was gunned down in the Tunisian beach massacre that claimed the lives of 30 Britons.