Chicago investigators yesterday studied a photograph from a Chicago drugstore where one of the Tylenol victims bought her tainted capsules to determine if a man in the photo resembles a suspect in an extortion attempt against the maker of Tylenol.

A spokesman for the task force investigating the seven cyanide deaths in Chicago said that special enhancement equipment will be used to examine the picture to see if the image of the man can be clarified. But he refused to make any identification of the individual in the picture.

Also in the picture is a young woman who resembles Paula Prince, one of the victims, as she is apparently buying a bottle of Tylenol. Investigators will not confirm her identity either.

"We have a great many photos of a great many people who may look like other people, and both for reasons of the case itself and because many innocent people are in those photographs, we have not released any of them up to now," said Mort Friedman, spokesman for the task force.

Investigators released the photo yesterday only after a local television station, WBBM-TV, showed the photo on the air and claimed in its news reports that police believed the man in the picture was James W. Lewis, who is being sought across the country on warrants in connection with a $1 million extortion attempt against McNeil Consumer Products Inc., the makers of Tylenol.

Until now, there had been no direct connection between the man sought on extortion charges in the case and whoever did the seven killings.

According to the unconfirmed report on WBBM, police have for several days been studying the photo and have asked those in the apartment building where James Lewis lived if they could identify the man in the photo. Some said they recognized Lewis, the TV report said.

Also yesterday, Illinois Attorney General Tyrone Fahner said investigators are closing in on Lewis and his wife, who he described as fugitives who together have used 20 different aliases.

Fahner, who is leading the Tylenol killings investigation, said that the couple is still the "primary lead" in the three-week-old case.

Though the two have not been considered direct suspects in the seven killings, Fahner said he has not ruled out that possibility yet.

He said the search for Lewis, linked by fingerprints and handwriting samples to the extortion letter to McNeil, which is a subsidiary of Johnson & Johnson Products Inc., has been narrowed.

"Based on the credible information we have, we think we have a good chance of finding them," Fahner said of Lewis, 36, and his wife, Leann, 35.

"We are looking in a select number of areas," Fahner said.

Fahner said investigators have received tips on an "extrordinary number of sightings" since warrants for the pair were issued last week.

Fahner said Lewis was known by the adopted name of Theodore Elmer Wilson until he was in high school.