Two motorists have ignored the no entry signs on the Mountain Road.
Both drove past the signs within the space of an hour on Sunday.
The A18 Mountain Road is one way to traffic from Ramsey hairpin to Creg-ny-Baa until June 13.
Police are warning people to pay attention to signage.
They said: ‘Unfortunately in the last hour two people have driven past these heading off from the Creg ny Baa towards Kates Cottage.
‘Fortunately we have a police unit nearby who could stop them.
‘They have been dealt with accordingly.’