The group of men, who were reported to have Irish accents and drive a black pick-up-truck, were said to have travelled to the Island without a licence to carry out this work.
Pictured: A copy of the card given out by the roofers.
Police said they were working with Customs and Immigration and the Population Office to deal with them appropriately.
They urged islanders not to engage with them, or allow them to do any work on their property.