Aneurin Bevan University Health Board says it will now be taking legal proceedings to take back possession of the car park at Royal Gwent Hospital in Newport.
It says it had asked a group of travellers from France, who have parked caravans in a section of the staff car park, to leave by 4pm today - but they are still on site.
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A night of two halves - cold under clear skies in the south, with cloud and mist around the hills in the north!
The partner of a man critically injured in a crash in Cardiff has appealed for witnesses to come forward.
There are calls for the Welsh Government to change the law to force councils to collect rubbish at least once a fortnight.