No Weapon Found in Search of Chicago Field : Probe: A wooded lot near O’Hare International Airport is combed for possible evidence in Simpson case. A tipster reported seeing him there the day after killings.

It is an anonymous spit of wood in an O’Hare International Airport flight path, littered with trash and clotted with weeds and elephant grass, a summertime fortress for suburban rat packs and a nocturnal haunt for a homeless man who sleeps under the stars.

For the past week, the lot, brimming with cottonwoods and jack pines, has become the most scrutinized parcel of real estate in the city, combed by Los Angeles and Chicago police detectives searching for a missing murder weapon and bloody clothes that might yield crucial clues in the Simpson murder case.

Trailing evidence-sniffing Rotweilers and wielding metal detectors, police covered the 20,000-square-foot lot for the third day Tuesday. For four hours, they rooted in vain through treehouses erected by neighborhood children and poked over the transient’s campsite.

By day’s end, the police and their dogs were gone, this time for good, they said, leaving without their sought-after knife or bloodied clothing.

“We’ve done the majority of the searching we expected to do here,” said Los Angeles Police Homicide Detective Bert Luper, whose walrus mustache and surfer’s shirts have become familiar images on Chicago nightly newscasts.

Luper declined to describe exactly what items detectives are seeking--although they are said to be hunting for the murder weapon and a jacket, shirt and shoes. He played down reports that the knife used in the murders had a 15-inch blade.

“It’s not quite that long,” he said.

Police began concentrating on the lot after a local ABC news affiliate broadcast reports from an anonymous tipster who insisted that he saw a figure who looked like Simpson emerge from a culvert at the edge of the wooded area about 7 a.m. June 13.

Simpson arrived at the O’Hare Plaza Hotel across from the lot at 6:30 that morning, within hours of the murders of his ex-wife, Nicole, and an acquaintance, waiter Ronald Goldman.

The tipster, who said he was driving out of a service station lot across the street from the O’Hare Plaza, has stuck to his story and elaborated on it in further calls to television reporter Dick Johnson.

“The guy said Simpson was wearing a touring hat and a golf shirt and pants,” said Johnson. The tipster, he added, has not talked directly to police, but his information has been relayed.

No other witnesses have come forward, Luper said. Those familiar with the wooded area say the time of the alleged sighting of Simpson is crucial to its veracity.

Tony Venturini, 66, owner of the service station, said that until 7 a.m., the streets near the wooded area are usually deserted. “You could walk an elephant down there and no one would notice,” he said.

After 7, the streets crowd quickly with commuters hurrying to a nearby elevated railway stop. If Simpson had gone to the woods after 7, Venturini said, it is likely he would have been seen by more than one witness.

“Between 7 and 8, it’s like Grand Central Station,” Venturini said. “You couldn’t come out of those woods without being noticed--especially someone like O.J.”

Last week, Pete Phillips, the former general manager of the O’Hare Plaza, said Simpson arrived at the hotel about 6:30 a.m., driven to the entrance by a Hertz rental car employee. Simpson was to play in a Hertz-sponsored golf outing. According to Phillips, Simpson went straight to his room on the ninth floor and was not seen until 8:30 a.m., when he came down in a panic and demanded a cab to the airport.

Besides the anonymous report of Simpson’s appearance in the woods, investigators have no firm proof that the former pro football star and television announcer was there on the morning of June 13.

Monday afternoon, police found a duffel bag and a pair of socks, which will be brought back to Los Angeles to be analyzed, but they acknowledged that the recovered items could easily have been discarded by someone else.

Venturini said the woods--just two blocks from the neighborhood where serial killer John Wayne Gacy killed and buried 27 youths--has been used for illegal dumping over the years.

Tim Frey, 12, who lives in the neighborhood, and a friend, Paul Rossi, 13, were among the steady stream of gawkers who trotted down the service road near O’Hare to watch police scramble under cottonwoods and jack pines.

The youths, who pedaled over on racing bikes, had a personal stake in the police activity. Chicago canine unit officers climbed up into all three of their tree forts in search of the missing knife.

By day’s end, their friends were crowding around Luper, begging him for autographs.

“Can you believe this?” Luper said, shaking his head in amazement. “I’m a cop.”

To James Turney, 14, it was only appropriate. He already had Simpson’s autograph on an old football card, bought for $35 at a sports memorabilia store. Now he wanted one from one of Simpson’s pursuers.

“This is history,” Turney said.

Hunt for Evidence

O.J. Simpson was staying at the O’Hare Plaza Hotel the morning the bodies were found. Police searched the field after a man who worked nearby said he had seen somebody resembling Simpson there.