Authorities said an elderly couple missing from a cruise ship may have jumped overboard in the waters off San Diego County.

Coast Guard crews have been looking in the waters off San Diego County this weekend for an elderly couple who may have jumped off a cruise ship as it steamed past the area.

A 90-year-old man and his 79-year-old wife are "presumed to have gone overboard" while on a Carnival Cruise that made a four-day trip from Long Beach to Santa Catalina Island and Ensenada, Mexico, before returning to Long Beach Friday night.

The couple's name has not been released. Their cabin door was double locked from the inside with a "do not disturb" sign on the handle, according to a statement from Carnival, and the door leading from the cabin to the balcony was unlocked.

The couple's personal belongings remained in the cabin, according to
Carnival. The last time the couple had been seen by the ship's crew was about 7:45 p.m. on Tuesday, according to a U.S. Coast Guard statement.

ABC7 reported that the couple had not used the card key to their room since Tuesday.

About 2,000 passengers were on the Carnival Paradise.

Laura Eimiller of the FBI said agents were collecting evidence and had not yet drawn any conclusions about the nature of the couple's disappearance.

"Whether we're dealing with a homicide, a suicide situation or an accidental death," Eimiller said to Los Angeles television station KABC, the FBI would not make any determination "until we have all the facts."

A Coast Guard crew in a C-130 airplane from the Sacramento air station searched the ocean between Ensenada, Catalina Island and Long Beach, but no sign of the bodies were found.