ATLANTA (AP) _ The FBI says it has images that appear to show a man with a hood sitting on a bench in Olympic Park about an hour before a bomb went off in that same spot.

The images of the man were taken at 12:19 a.m. on July 27, 1996. The agency also has a videotape taken nine minutes later of a parcel or backpack under the vacated bench.

The blast at about 1:20 a.m. killed one person and injured 100 others.

The FBI needs the public's help in finding images to fill in the nine-minute gap, said Jack Daulton, the agent heading the investigations of the bombing and two other bombings in Atlanta this year.

Daulton said it is hard to tell from the photo and video images of the man whether he is actually wearing a hood or if shadows make it appear that way.

``But the picture makes it look like he might have a hood on,'' Daulton said, noting that would be very unusual for a hot summer night.

Investigators are also intrigued because they are trying to identify a man wearing a hooded sweat shirt seen outside a suburban abortion clinic Jan. 16, hours before two bombs exploded there.

Seven people were injured at the clinic. Four people were injured about five weeks later when a bomb went off at an Atlanta nightclub that caters to homosexuals.

Investigators believe that all three bombings were carried out by the same person or group. A $500,000 reward initially offered in the Olympic Park bombing now includes the other two.

In addition to the 8,000 photographs and 1,300 videotapes examined so far, Daulton said investigators have looked at more than 500,000 documents to compare handwriting and style of a letter that claimed responsibility for the last two bombings. The letter sent to news organizations purportedly was from a group called the Army of God.

``We're still really trying to focus on the letter. We think the writer of the letter is involved somehow,'' Daulton said.