Meal beach in Burra remains cordoned off by police and coastguard officers after an unexploded ordnance device was discovered.
The marine location flare was found washed up with debris on Saturday night following a spate of bad weather.
In a statement Police Scotland have warned the device is believed to be “highly toxic”. A cordon has been set up around the beach in order to prevent anyone from entering the site.
An explosive ordnance disposal unit have been contacted, and are expected to attend the site on Wednesday to make the ordnance safe.
Police Scotland are urging people to stay away until the cordon has been removed and the area cleared.