The SA Marine Safety Authority on Monday said that it was still unclear exactly what led to a fishing vessel running aground on a Clifton beach.

Attempts to tow the ship back out to sea failed over the weekend.

It ran into trouble early on Saturday morning, in heavy fog.

The SA Marine Safety Authority's Dave Colly said the cause of the accident was still inclear.

"They do have radar, which would have been the main instrumentation which you would use in fog. If the radar was working, I can't imagine how they would have gotten into that situation."