Searchers on Sunday “unequivocally” identified an object spotted at the bottom of the Great Salt Lake as an aircraft of the general size and description of a Cessna 172, the type of plane that was reported missing Dec. 29, according to the Box Elder County sheriff’s office.

Severe equipment issues and fog postponed a dive planned for Sunday to recover the airplane, the sheriff’s office said in a news release. The time for a new dive, in the northern arm of the lake, is yet to be determined.

“Several factors need to be considered and discussions with personnel need to take place to make that decision,” the release says.

The missing airplane took off from Ogden Hinckley Airport about 3:30 p.m. Dec. 29. Pilot Denny Mansell, 71, and passenger Peter Ellis, 74, planned to fly to the Promontory area to see the trains at the Golden Spike National Historic Site.

Authorities were notified that night that the plane was overdue and an air and ground search was launched. The search area was narrowed to a small section of the lake based on tips and an analysis of the radar data from the Cessna before the loss of its signal.

An object believed to be an airplane surrounded by debris was spotted Saturday morning resting on the bottom of the lake in approximately 14 feet of water, the news release says. The weather had deteriorated Saturday so the dive was scheduled for Sunday, when it was once again postponed.

The release says the agencies that have participated in the search efforts are the Box Elder County sheriff, BE Search and Rescue, Utah Department of Public Safety, Civil Air Patrol, Box Elder Communications Center, Utah Division of Natural Resources and Weber County Scuba/Search and Rescue.