Another day, another set of Zodiac-killer tips — this time hailing from as far away as Montana.

Two file drawers at The Chronicle are stuffed with such tips, but few as voluminous as the one mailed this week from John Cameron, a retired homicide detective from Great Falls, Mont. He sent a 207-page report, accompanied by several hundred exhibits and discussions of the bewildering messages Zodiac sent to police and the media during his unsolved murder spree in the Bay Area four decades ago.

The gist of it all, Cameron said, is that the Zodiac is 77-year-old Edward Wayne Edwards — who is alive and unwell in prison in Ohio, where he is serving two life terms in prison for a 1977 double murder. Cameron said he concluded, after a summer-long investigation, that Edwards murdered as the Zodiac “to show to the world that Portland, Ore., authorities arrested the wrong people” for his 1960 slaying of a couple parked on a lovers lane.

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Edwards, Cameron said, went all over the country killing people over the past half-century, and was stopped only a year ago when he was arrested for the Ohio murders.

“This guy will turn out to be the most prolific serial killer that ever was,” Cameron told The Chronicle. “He was a master at creating alibis and false birth certificates, and he killed everywhere, from one end of the country to the other.”

The Zodiac killed at least five people in 1968 and 1969 in the Bay Area, and he taunted the press — including The Chronicle — and investigators with cryptic, boasting letters. He is the most infamous uncaught killer in American crime annals.

Cameron, who is an analyst for the Montana Board of Pardons and Parole, said he sent his Zodiac package to a dozen law enforcement agencies that have connections with the Zodiac or Edwards cases, including the San Francisco Police Department and the FBI.

“We haven’t received anything yet, but we check out any new leads,” said San Francisco police Lt. Lyn Tomioka.

Also dispatched urgently — and they are always urgent, when it comes to the Zodiac case — to The Chronicle this week was a set of Zodiac cipher decryptions that purport to prove that the killer was spelling out “Screw You” in the shape of male and female private parts, to taunt police. The tipster asked to remain anonymous.

These new leads join a giant pile of others of late, including those supposedly proving the killer is a composite of several police officers, is a prominent local poet, is a neighbor (lots of those, from coast to coast) or is the Unabomber (a persistent theory for years).

And there is last year’s claim from Orange County real estate agent Deborah Perez that her father, Guy Ward Hendrickson, was the Zodiac. This ignited angry denials from Perez’s stepsister, Janice Hendrickson of the Bay Area — and a still-raging debate online from the hundreds of amateur Zodiac sleuths who stake out allegiances to one sister or another, not to mention the other hundreds of would-be Zodiac suspects.

Tomioka said her department hasn’t closed the book on the Hendrickson lead. But that doesn’t mean he’s the bad guy.

“She (Perez) did provide us with some items that we followed up on, and we’re still investigating,” Tomioka said.