Highland Park Fire Chief Larry Amidei said the accident was reported about 10 p.m.
Two 19-year-old men were sliding on a bluff for fun when they fell onto the beach, Battalion Chief Ryan Hughes said.
The dense fog in the area made locating the men and the rescue difficult.
Emergency crews had to hoist one of the men up with ropes because he had broken his leg. The other was lifted in a rescue stretcher.