The Deputy State Pathologist is due in Letterkenny this afternoon to carry out a post-mortem examination on the body discovered near Redcastle last evening.
The badly decomposed remains were discovered on the shore of Lough Foyle shortly after 4 o'clock, with gardai predicting the body may have been in the water for between four and five months.
Identifying the body is now the priority.
Gardai say there are no reports of missing people in Donegal, but they are in contact with the PSNI's missing persons office in Derry, and they are awaiting dental records and DNA samples from a number of missing people so that comparisons can be made.
Superintendent Kevin English earlier gave the background to the discovery: