New details released in unsolved 'Doodler' serial killer case from 1970s originally appeared on abcnews.go.com

In the decades-long search for a San Francisco serial killer, police released new details Wednesday, including an updated photo of the suspect and a 911 call, as well as announcing a new reward for information leading to the killer’s arrest.

Gay men in San Francisco were targeted in the 1970's by a serial killer known as “The Doodler.”

The Doodler is believed to be responsible for five murders and possibly more, authorities said.

PHOTO: Gay men in San Francisco were targeted by the serial killer known as the Doodler in the 1970's. (San Francisco Police Department)

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The killings occurred between January 1974 and June 1975, "gripping the community," officials said. The victims -- all gay white men in San Francisco -- suffered similar injuries including stab wounds to the upper chest and back, officials said.

One victim who survived his attack said that when he met the suspect at a gay bar, he was drawing caricatures on a piece of paper. This led to the "Doodler" nickname, San Francisco police officials told reporters Wednesday.

The surviving victim provided a sketch of the suspect, who was described as an African-American man between the ages of 19 to 25.

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That original sketch, created in 1975, was released by police Wednesday alongside a progression sketch of what the suspect may look like today, officials said.

PHOTO: Gay men in San Francisco were targeted by the serial killer known as the Doodler in the 1970's. (San Francisco Police Department)

A $100,000 reward is being offered to anyone who can identify the suspected killer based on either sketch, officials said.

On Wednesday, the police also released audio from a 911 caller who found the body of the first murder victim in January 1974.

The witness who found the body did not want to provide his name to the 911 dispatcher at the time, officials said. Authorities are now urging anyone who recognizes the voice to call them as they are looking to speak to this man about what he saw.

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As the unsolved mystery moves further into the modern age, DNA evidence has been submitted from a "couple" of the five homicides, and investigators are awaiting results from those tests, authorities said Wednesday.

A person of interest identified in 1976 remains a person of interest in the case, officials said Wednesday, adding that they are looking to speak with a psychiatrist who possibly treated that person in 1976. Police have not released a name.

That psychiatrist likely worked in the East Bay, possibly with last name “Priest,” authorities said, urging anyone who might know this psychiatrist's identity to come forward.

Anyone with information can call the San Francisco police at 1-415-575-4444.