CALHOUN, Ga. (AP) — Four people killed in a small jet crash in the Georgia mountains have been identified.

The deceased included three men and one woman, Gordon County Deputy Coroner Christy Nicholson said Tuesday.  She identified them as the pilot, Roy Smith, 68, of Fayetteville, Georgia; his son, Morgen Smith, 25, of Atlanta; Morgen Smith’s girlfriend, Savannah Sims, 23, of Atlanta; and the co-pilot, Raymond Sluk, 62, of Senoia, Georgia.

There was snow in north Georgia around the time the Cessna 501 Citation crashed shortly after 10 a.m. Saturday in a remote part of Gordon County, northwest of Atlanta, authorities said. The wreckage was found hours later in a wooded area that emergency crews were only able to reach on foot.

The National Transportation Safety Board is investigating. Nicholson said that the agency would release further details later about the crash.

Weather conditions are among many factors that will be investigated in coming days and weeks, said Heidi Kemner, an air safety investigator with the NTSB. Investigators also will look at the pilot’s record and training as well as the aircraft’s maintenance, NTSB spokesman Terry Williams said.

It could be up to 18 months before a factual report is ready and a determination on cause is made, investigators said.

The plane went missing from radar shortly after takeoff from an airport in the Atlanta suburb of Peachtree City. The plane disappeared around 10:10 a.m. Saturday about 50 miles (80 kilometers) north of Atlanta after departing, authorities said. It was en route to Nashville, Tennessee, FAA spokeswoman Kathleen Bergen said Sunday.