Coronavirus testing was abandoned in Watford on Thursday, June 11, when travellers set up a camp in a car park.
The drive-thru testing centre at Watford Leisure Centre had been opened on Thursdays and Sundays, but people with a test booked will now have to go to the temporary base in Apsley, Hemel Hempstead, which is seven miles away.
Watford Borough Council says it has started legal proceedings to move on the travellers who arrived on Wednesday night.
In a statement, Herts Valleys Clinical Commissioning Group said: “On Wednesday evening, a group of travellers arrived on the site that was designated for the mobile testing unit for Thursday.
“This means that we have had to change arrangements and for Thursday (yesterday) and Sunday, testing will be carried out on the Apsley site in Hemel Hempstead. The public are being informed and being redirected. The landowner is aware.”