Searchers are examining more than 2,000 aerial photographs taken of the West Lafayette area as they seek clues to the disappearance of a Purdue University freshman.

Wade Steffey, 19, of Bloomington hasn't been seen since Jan. 13, when he left a fraternity party on the north side of campus.

He was reported missing after friends returned from the school's three-day break for the Martin Luther King Jr. holiday and could not find him.

The aerial photographs are being analyzed by Sean Henady of Lite Imaging. Henady recently helped police find the body of Chuck Rickey, a 36-year old man from Carmel who had been missing for six weeks.

About 60 volunteers, assisted by dogs, conducted a ground search for Steffey on Sunday afternoon, said organizer Patti Bishop of the group IN Hope.

"It was successful," Bishop said. "And when we say successful, it doesn't mean we found Wade or his possessions. A search can be successful by covering a lot of ground and covering it thoroughly."

Dale Steffey, Wade's father, said Sunday's search was another necessary step. "Intellectually I know we just have to keep searching," he said. "But emotionally, it's very difficult to walk along a creek bed and expect to find my son."