Pacific walruses are beaching on Northwest Alaska shores, peppered with bleeding skin legions that have been observed on dying ringed seals in Arctic Alaska, according to federal biologists.

A mysterious disease, possibly a virus, has afflicted ring seals along Alaska's coast, killing scores of them since July, local and federal agencies said on Thursday.

Biologists are trying to determine what's ailing ringed seals that live off Alaska's Arctic coast. Scores of seals stranded on beaches this summer appeared to have skin lesions, and dozens have died.