STONE MOUNTAIN -- Authorities on Monday released the sketches of two persons of interest wanted for questioning in the weekend death of an attendant at Stone Mountain Park who was fatally shot.

The sketches are part of an intensifying effort to find the killers of Anita Redmon, 63, who was gunned down at 12:30 a.m. Saturday during an apparent robbery attempt.

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A $20,000 reward is being offered for information in the slaying of Redmon, whose body was found in the gatehouse at the popular tourist attraction.

Authorities have said the killing was the first such incident in the history of the park. Redmon, who served with the Doraville Police Department for 25 years before retiring in 1999, began working at the park just three months ago.

In addition to the release of the composite drawings, authorities used prison workers to clear away the brush from the entrance in an effort to unearth more clues in the case.

"We figured that possibly the perpetrator ran down this road and possibly threw a weapon into the kudzu," said John Bankhead, a spokesman for the Georgia Bureau of Investigation, which is also investigating the incident.

The woman was on the phone with park police dispatch when she signaled that she was being robbed. A witness saw a lone man running down the road after the shooting.

The shooting has stunned the park community.

"It's hit very close to home," said park police Chief Chuck Kelley. "This is a case we will not rest until we've solved."

Anyone with information was asked to call park police at (770) 498-5675.

Channel 2 Action News reporter Ross Cavitt contributed to this report.