The Medical Examiner's Office is conducting an autopsy to determine the cause of death of a kayaker whose body was found face down in the mud off Cudjoe Key Monday evening.

The man's kayak was found nearby, off the Tarpon Belly Keys, and a vehicle believed to belong to him was found parked on Blimp Road.

A couple on a sailboat spotted the body at 6:15 p.m.

The Monroe County Sheriff's Office said it has a tentative identification of the man and will release his name once they have confirmed it and notified his family.

No signs of foul play were evident, they said.