Authorities searching for a missing plane in the rugged north Georgia mountains are focusing on 10 "areas of interest."

Maj. Paige Joyner of the Georgia Wing of the Civil Air Patrol said the focus is on these areas because of tips searchers have received.

The plane with four people on board was reported missing Monday.

The Beech 35  departed the Ellijay airport about 80 miles north of Atlanta around 10:30 a.m. Monday "for a sightseeing trip within a 50-mile radius of the airport," Federal Aviation Administration spokeswoman Kathleen Bergen told the AJC.

"The family called the airport when the aircraft didn't return as expected," Bergen said. She said the flight had no contact with air traffic controllers.

Joyner, of the Georgia Wing of the Civil Air Patrol, said help from the public has been phenomenal. She said some people thought they saw the aircraft, but searchers so far have not come up with anything concrete.

Joyner said Tuesday that more than 100 people covered 800 square miles Tuesday, searching from the air and on the ground, but were unable to find the plane.

The Civil Air Patrol, local emergency management, Gilmer County sheriff and police departments and the Georgia State Patrol were involved in the search, Joyner said.

The plane's pilot, identified as Phil Keith, is from Ohio and the three passengers from Gilmer County, Channel 2 Action News reported. They were in Ellijay for their high school 50th reunion, Gilmer County Fire Chief Tony Pritchett told Channel 2. Two of the passengers were identified as Patricia Smith and Mattie Pierce, Channel 2 reported.

The Beech 35, also called a Beechcraft Bonanza, is a single-engine plane that can seat up to six people.

Last Wednesday, a small plane flying from Fulton County Airport in Atlanta to Hazard, Ky., crashed in a remote area of the western North Carolina mountains.

The pilot of that twin-engine plane, Matthew Shuey, was killed, along with his three passengers, Tiffany Maggard, 23, Kassie Robinson, 22 and Miranda Morgan, 20.

The three women were all either current or former students at Alice Lloyd College in Pippa Passes, Ky.

-- The Associated Press contributed to this article.