Travellers have moved onto the site a former hospital in Drayton.
It is understood that a group parked up on land off Drayton High Road, near Norwich, on Monday evening (April 23).
The land, which was previously the site of the former David Rice Hospital, is owned by the Lind Trust.
The trust was granted outline planning permission by Broadland District Council in October last year to build 29 homes on the site.
Graham Dacre, who runs the trust, confirmed action would be taken to move the group on.
Norfolk Police said it was aware of the encampment and was working with 'partners' to resolve the situation.
It comes as travellers set up camp on the car park of the former Lidl store in Norwich over the weekend.
It is understood that they arrived at the site, on Copenhagen Way, near Aylsham Road, between Saturday, April 21 and Sunday, April 22.
The former store closed at the end of January this year after the company announced it was opening another supermarket 400m away on Aylsham Road.
A spokesman for Lidl said: 'We can confirm that bailiffs have been instructed to serve a notice of eviction to the trespassers that have occupied our land on Copenhagen Way.'
A police spokesman said: 'Norfolk Police are aware of a traveller encampment at the disused Lidl site in Copenhagen Way, Norwich, and we are working with partners.'
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