In late April, media around the world, including CBC News and The Globe and Mail, picked up on a story that a vengeful dentist in Poland had extracted all the teeth of an ex-boyfriend. According to Polish media and MSNBC, it didn't happen.

The story appears to have originated with the Daily Mail in London on April 27. Reporter Simon Tomlinson quotes the dentist, Anna Mackowiak, and her ex, Marek Olszewski. Many media organizations pointed back to the original article. Some even presented the story as their own without checking the facts, complete with the quotes — and sometimes, even a photo.

A number of Polish media did check and, within days of the original Daily Mail article, published information that suggests there is nothing to the story. No dentist or doctor named Anna Mackowiak practices in Wroclaw, no police records were found about the case. Experts were interviewed, but nothing that could corroborate the story turned up.

Dentistry professor Marek Zietek of the Medical University of Wroclaw could recall just one case, from 30 years ago, in which a female patient's teeth were pulled, but that was at her request, and she was later found to be insane, the Gazeta Wroclawska reported on May 2.

It took a week for western media to catch up to what Polish media had been reporting. And that is probably a result of a story on MSNBC.com on May 8.

When MSNBC asked Tomlinson about the origin of his story, he told them "I've drawn a bit of a blank," adding that his "news desk isn’t sure where exactly it came from."

CBC News searched the internet for stories that contained the names of the dentist and patient that dated from before April 27 and found none.

After the CBC's story was published, the Daily Mail's website, Mail Online, removed the story without explanation. The newspaper has not issued a correction on its website, as of this writing. (That Gazeta Wroclawska story includes an image of the Mail Online story.)

The New York Sun series claimed there were man-bats (vespertilio-homo) on the moon. This image is from an 1836 edition of the moon series in Italian. (Delle Scoperte Fatte Nella Luna del Dottor Giovanni Herschel/New York Public Library)

News media over the years have reported many stories that turned out to be false. Here are five front-page fabrications from among the better known.

The great moon hoax, 1835

The New York Sun newspaper ran a series of six stories in 1835 that said an eminent British astronomer had observed life on the moon, using an incredible new telescope. The creatures included "man-bats" and beavers that walked on two feet and lived in huts "constructed better and higher than those of many tribes of human savages."

The public initially believed the Sun's stories. Two years later, Asa Greene, the editor of a rival newspaper, wrote about what he termed an innocent fiction: "There were, indeed, a few sceptics; but to venture to express a doubt of the genuineness of the great lunar discoveries was considered almost as heinous a sin as to question the truth of revelation."

Jacko Hoax, 1884

Some believe this film image, shot in California in 1967, is of a female sasquatch. (Sasquatch Research Project /Associated Press)

Victoria's Daily Colonist newspaper (today the Times Colonist) reported on July 4, 1884, that a "half-man, half beast," creature had been captured by railway workers near Yale, B.C. "What is it? A strange creature captured above Yale. A British Columbia Gorilla" was the headline.

A few days later the Mainland Guardian reported that the Colonist had been duped. Another newspaper reported that 200 people who went to view the creature at the jail where it was reportedly held saw nothing of the sort.

However, decades later, the original story would be cited by bigfoot/sasquatch believers as early proof of a sighting. The original story has made it into three U.S. television documentaries.

Jimmy's World, by Janet Cooke, 1980

On Sept. 28, 1980, The Washington Post ran a story by reporter Janet Cooke on page one that began, "Jimmy is 8 years old and a third-generation heroin addict, a precocious little boy with sandy hair..."

Cooke would receive a Pulitzer prize for feature writing the following year (she was nominated by Bob Woodward, her editor).

Former New York Times reporter Jayson Blair speaks to an audience in New York's Harlem neighborhood March 12, 2004. (Jennifer Szymaszek/Associated Press)

Two days after she received the prize, the Post would admit the article was fraudulent. This correction now appears above the story: "The following article is not factually correct and is a fabrication by the author."

Jayson Blair, 1997-2003

Jayson Blair became a reporter at The New York Times in 1999, but his fabrications date back to at least 1997 when he was an award-winning student journalist at the University of Maryland. During his years at the Times, which the newspaper called "a low point" in its long history, he fabricated details and plagiarized in numerous stories.

Several of those stories were about the 2002 Beltway sniper attacks in the Washington D.C. area in 2002 (at least 10 people died; John Lee Muhammad was executed in 2009). During the Iraq war, Blair also claimed to have covered the Jessica Lynch story from her home town, even though he hadn't travelled there.

Balloon boy, 2009

Six-year-old Falcon Heene sits in the box of his family's pickup truck outside their home after he was found hiding in a garage. ((avid Zalubowski/Associated Press)

Falcon Heene, a six-year-old in Colorado was believed to be inside a helium balloon that had floated away from his family's backyard on Oct. 15, 2009.

At least his parents told the authorities they were certain that was the situation. A media frenzy soon began, with live TV following the balloon's flight. After 80 km it landed but no one was inside. Had Falcon fallen out?

A few hours later, Falcon emerged from the attic of the family's garage.

Later that evening, during an interview with the Heene family on CNN, Falcon said he didn't come out of the attic when called because they were "doing this for the show." That was apparently a reference to plans for a reality show. It was also the first 'aha' moment for the local sheriff. Heene's parents would soon plead guilty in the case.