VICTORIA -- Police have gone quiet and a website has pulled postings in the wake of a social media frenzy about the latest development in an historic and infamous cold case involving a four-year-old missing boy.

Victoria police announced Wednesday they're collecting DNA from a B.C. man identified by a tip as the possible grown-up Michael Dunahee, who vanished without a trace from a school play area where he was with his parents nearby March 24, 1991.

Investigators have been careful to say they believe it is unlikely the man is Dunahee. On the Facebook page "We Will Never Forget Michael Dunahee", someone identifying themselves as Dunahee's sibling wrote the tests are a "formality."

"We do not have any results yet," said the Facebook post. "We have been told that this is a formality and the police use the DNA so they can be 100 per cent before dismissing any tips."

But the police and the Facebook post couldn't dismiss the possibility that Dunahee might have finally been found alive, prompting breathless speculation.

Tweets by individuals and media organizations Thursday included "Surrey man could be missing child," "Rumours swirl that man could be B.C. child who disappeared in 1991," "Michael Dunahee, can it be?"

News stories published side-by-side photos, highlighting the uncanny resemblance between the adult who said in an online post he was approached by police for his DNA and the police composite sketch of what Dunahee would look like as an adult.

"I never once said I am him, but I'm obviously curious if they contacted me and want a DNA test," said the posting on a fan forum run by canucks.com, and quoted extensively in media reports.

That site was taken down Thursday morning, replaced with a note from the administrator.

"A member had posted (in confidence between the membership), and that information was taken outside of the forums and distributed," wrote the administrator. "In respect to this person's privacy, this matter is now closed in order to keep in line with that."

But the posting was reproduced on the website vancitybuzz.com.

The story has now appeared across the country, running in national newspapers, metropolitan dailies and the websites of broadcasters and community papers.

The story has always generated widespread interest, a set of circumstances that appear in any parent's worst nightmare.

Crystal Dunahee, the boy's mother, appeared on the "Geraldo Rivera" talk show with John Walsh, the host of America's Most Wanted," in January 1993.

After meeting a psychic on a Seattle, Wash., television talk show, she travelled to Torrence, Calif., the following year to chase down a lead.

Bruce Dunahee, the boy's father, also said at the time he had travelled to Wyoming with a psychic to search for his son.

In February, 2005, Victoria police announced they hired some retired serious-crime investigators to review five cases, including the Dunahee's.

Victoria police announced in March 2006 a reward of up to $100,000 for information that leads to the successful conclusion of the case.

The investigation headed to Milwaukee, Wis., in January 2009. Media reports at the time indicated police had found a poster of Dunahee in the home of a man who had died of natural causes but confessed to his psychiatrist to killing two children in the late 1950s.

Last November, author Valerie Green published a new book on the case. The book's cover displayed photos of Dunahee just before his disappearance and a composite sketch of what he'd look like as a 22-year-old man.

On vancitybuzz.com, the unidentified man said he had been contacted by Victoria police who had taken his blood, was "freaked out," and even began to question his own identity, saying he had no memories prior to Grade 1.

"Think about this for a second: you second guess everything in a short period of time. This is really tough."

Making matters worse, he added, was the recent death of his mother who kept him separated from his family.

"I don't know what to think," he added. "Part of me thinks it could be, but others don't. I just want them to take my DNA and figure this out."