According to authorities, the search ended in the waters off of San Diego County Saturday morning.
The couple, whose names were not released, are believed to be a 90-year-old man and his 79-year-old wife.
Crews searched throughout the night, covering the route of the Carnival Paradise ship, which started in Long Beach and stopped in Santa Catalina Island and Ensenada. The couple were aboard the ship when it left Monday, but they were missing when it returned to port early Friday.According to ship officials, the couple's cabin door was double-locked from the inside with a "Do Not Disturb" sign on the handle. Their belongings were discovered inside and the door heading from the cabin to the private balcony was unlocked.