Justin Bieber fans take note: The pop megastar does not have cancer.

As Mashable notes, a Twitter hoax claiming the pop icon was diagnosed with cancer swept through the Internet this week, giving Beliebers everywhere a collective heart attack.

The hoax reportedly started on Oct. 22 with a screenshot of what appeared to be a tweet from Entertainment Tonight's official Twitter account, the tech website writes. The fake tweet announced that Bieber had been "diagnosed with cancer" and "suggested that fans go #BaldforBieber" in support of the pop sensation.

"Pop Star Justin Bieber was diagnosed with cancer earlier this morning. Bieber fans are shaving their heads to show their support," the tweet read, according to Gawker.

Before long, tribute videos, Facebook pages and a website -- BaldforBieber.com -- were launched, fueling the claim.

On BaldforBieber.com, for instance, there are Photoshopped tweets from the "Baby" crooner talking about his "diagnosis," as well as a photo gallery showing "fans" who have shaved their heads to in support of the pop star.

According to NBC's Today, many of Bieber's fans fell for the hoax, with more than 900 people tweeting #BaldforBieber over the past week.

Fortunately, however, the potentially disastrous prank was short-lived.

On Reddit Friday, it was revealed that the whole ruse had likely been created by trolls on 4Chan, the online bulletin board.

"People killed the joke pretty quickly by tweeting 'LOL Best PRANK EVER GO 4CHAN #baldforbieber,'" wrote "thelowend6."

Redditor "ErroneousDylan," who claims to have been part of the conspiracy, added:

I was there when we started this...Somebody made a few Twitter accounts, we edited Wikipedia, we spammed chat rooms, and we even posted here on Reddit (but it was deleted for lack of evidence). Somebody made a few fake news posts too which were convincing but without a link it wasn't strong enough.

Though several sites have "claimed that a few Beliebers were ultimately fooled by the ruse" (going so far as to shave their heads), there appears to be "no evidence of this on Twitter or elsewhere," Today writes.

On Friday, flocks of people took to Twitter to express their thoughts on the #BaldforBieber hoax:

#baldforbieber please tell me people didn't actually shave their head before source checking this rumor....? — Dr. SarBear... (@SarahMcGuireJB) October 26, 2012

#BaldForBieber is disgusting. Cancer is not a thing to be joke about but LOL at the Beliebers who literally shaved their heads — Kirti (@_Kirti__) October 26, 2012

Bieber himself hasn't mentioned the hoax, Today notes. However, his bodyguard Kenny Hamilton was unambiguous in squashing the rumors.

@KeithSchwartz48 no — Kenny Hamilton (@KennyHamilton) October 26, 2012