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 largely dry day with just a risk of isolated showers especially in the north and west. Heavy and persistent rain overnight.
On a visit to Wales Labour leader Ed Miliband sets out a ten-point promise on how his party will deal with immigration.
One of the men was described as carrying an object similar to a handgun in the bakery delivery van hold-up