Gardai have received a number of reports of sheep being stolen in the Fanad and Dunlewey areas.
A number of sheep have been stolen in those areas over the past few weeks and they have been stolen in small quantities.
Gardai say these thefts are taking place during the hours of darkness.
“We ask farmers to be vigilant and to report any such thefts to Gardaí.
“We ask all residents in those areas to report any suspicious activity and any suspicious vehicles (vans in particular) to Gardaí immediately,” said a Garda spokesperson.