The sheriff's department had received 100 calls and numerous e-mails by Wednesday after asking for help identifying women in dozens of decades-old photos taken by a double murderer who implied to his jury he'd killed others.

The photos had languished in an evidence archive for 22 years, until a cold case investigator rediscovered it last month and looked through its contents: about 50 images of young women, many of them scantily clad and striking poses like amateur models.

The photographer was on death row for killing two women, both aspiring models, in the 1980s.

Investigators reopened the file and set out to find the women in the pictures, authorities said Tuesday.

Detectives are investigating whether the women were raped or killed between 1975 and 1984 by William Richard Bradford, said Los Angeles County sheriff's officials, who posted numbered photographs of the women on a department Web site in hope that the public could help account for them.

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The case could lead outside California. Bradford has spent time in Illinois, Texas, Florida, Michigan, Oregon and elsewhere.

"We could have victims theoretically all over the country," said sheriff's Capt. Ray Peavy.

One woman in the photos, No. 28, was identified as Donnalee Campbell Duhamel, 31, whose decapitated body was found in a Malibu canyon in 1978 a few days after meeting Bradford at a bar, Peavy said.

"What we have here is a very large group of pictures of women that we do not know for the most part who they are," Peavy said. Some were Bradford's wives and ex-wives, but the majority are unknown to authorities.

"Many of them could have likely been homicide victims themselves," Peavy said. "Many of them may have just been women that he met in bars and took home and took photographs of."

Following a televised news conference in which the photos were shown, phone calls began arriving from people claiming to be women in the photos or having information about them, said sheriff's Sgt. Alfredo Castro.

"The phone hasn't stopped ringing," he said. "I'm pretty sure we're going to identify a lot of them soon."

In all, investigators had received tips placing names to 12 of the women, though none has been confirmed yet, sheriff's Lt. Debra Lenhart said Wednesday.

In the 1970s and '80s, Bradford, now 60, posed as a freelance photographer in the West Los Angeles area, taking photos of women he met at bars and car races, according to information on the department Web site. He worked as a handyman and sometimes hung out with a motorcycle gang, officers said.

The photographs and film were seized when search warrants were served on Bradford's home at the time of his arrest in 1984, Peavy said.

"Those items went into a case file. That case file, quite frankly nothing was really done with those photographs up until right now," Peavy said.

Bradford was convicted in 1987 of first-degree murder in the stranglings of Shari Miller, 21, who he met in a bar, and Tracey Campbell, 15, a neighbor. Prosecutors said he lured them into accompanying him with promises to help their modeling careers.

Miller's body was found in a West Los Angeles parking lot in July 1984, while Tracey's decomposed body was found in August 1984 at a campsite 28 miles east of Lancaster, a high desert area north of Los Angeles.

In the penalty phase of his trial, Bradford asked the jury to sentence him to death: "Think of how many you don't even know about," he told jurors.

It was unclear whether Bradford was currently represented by an attorney. An attorney who represented him in the past, Robert R. Bryan, did not return a call seeking comment Tuesday.

Peavy said it's possible the remaining unidentified women were alive and well, though he wasn't hopeful.

"My gut instinct," he said, alluding to a collage of the women's photos at the sheriff's homicide office, "is that there are probably a substantial number of victims on that board."