A rare moment of civility broke out on the Internet Monday, as the troublemaking geeks of 4chan.org called off a planned attack on telecommunications giant AT&T.

The Texas-based company had made the mistake of blocking many of its home high-speed Internet clients from reaching the lewd, crude 4chan imageboard Sunday.

Many bloggers were quick to decry the act as a form of censorship, but the real reason was duller: 4chan was the victim of a still-ongoing cyberattack, and AT&T was just trying to protect its servers.

AT&T lifted the block of 4chan overnight, and as one 4chan-related Web site that had quickly sprung up to plan a "raid" said, "All rioting/'war'/protests have been suspended for the time being."

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"Beginning Friday, an AT&T customer was impacted by a denial-of-service attack stemming from IP addresses connected to img.4chan.org," read a statement issued by AT&T Monday morning. "To prevent this attack from disrupting service for the impacted AT&T customer, and to prevent the attack from spreading to impact our other customers, AT&T temporarily blocked access to the IP addresses in question for our customers.

"This action was in no way related to the content at img.4chan.org; our focus was on protecting our customers from malicious traffic."

Later that same day, "moot," aka Christopher Poole, the 20-something owner and very hands-off administrator of 4chan, concurred in a blog posting.

"This wasn't a sinister act of censorship, but rather a bit of a mistake and a poorly executed, disproportionate response on AT&T's part," he wrote. "Whoever pulled the trigger on blackholing the site probably didn't anticipate (nor intend) the consequences of doing so."

While the block was still going on, some 4chan users did begin to retaliate.

The office phone number and purported e-mail address of AT&T CEO Randall Stephenson were quickly posted on the site's infamous /b/ board, and a report that Stephenson had died — archived here — was posted to CNN's user-generated-content iReport Web site and quickly removed.

"4chan Anonymous /b/rothers we are heading down a path that will lead either to one of the biggest victories on /b/ for this year , or total annihilation of a percentage of our userbase by AT&T," read one post later reproduced on a 4chan-related online encyclopedia. "If you are not willing to take on AT&T then at least let it be known this censorship is going on by spreading it throughout the internet."

More impressive was the fear among tech bloggers that a massive 4chan counterattack was about to begin.

"[AT&T] surely knows that going after the most expert and vindictive group of internet hackers would mean all-out war," noted the Times of London's Tech Central blog.

"AT&T has just opened perhaps the most vindictive, messy can of worms it could have possibly found," said TechCrunch. "Blocking any site is an extreme breach of user trust, but the decision to block 4chan in particular just seems stupid. Expect the web equivalent of rioting if this doesn't change soon."

Well, that didn't quite happen. The Twitter feed "4chan4ever," apparently set up to plan retaliation, began to run out of steam Monday, promising only to "send out info later in the day."

AT&T spokesman Michael Coe told FOXNews.com there'd been no unusual activity on AT&T's broadband network.

Meanwhile, 4chan continued to be subject to a distributed denial-of-service (DDoS) attack, similar to the attack that knocked several U.S. and South Korean government Web sites earlier this month. While still accessible, the site was much slower than usual.

That means 4chan's servers were being flooded with millions of useless requests for data — and due to the specific nature of the attack, millions of unsolicited messages were being bounced back to AT&T's servers.

Some 4chan users blamed the DDoS attack on Anontalk.com, a Sweden-based online "bulletin board" that lets users post completely anonymously (as does 4chan) and which seems to be a frequent target of 4chan ire.

As is the case with many DDoS attacks, the true culprit may never be known.