CHICAGO (CBS) — Cook County Sheriff Tom Dart could know this week whether one or more of John Wayne Gacy’s eight previously unidentified victims has now been tentatively identified.

“We’re getting closer,” said Dart. “Put it that way.”

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Sheriff Dart says DNA swabs from six families have been submitted. And he says four or five other families will get their DNA tested next.

“We’re anticipating today or tomorrow, some type of preliminary analysis that there is or there is not a match on some of the initial ones,” Dart said.

Since Dart asked last month for people to come forward if they thought a family member might have been a Gacy victim, there have been 150 leads – including 50 or 55 considered credible.

John Wayne Gacy was accused of murdering at least 33 young men and boys in the 1970s.

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