A massive DDoS cyber attack that disabled many prominent online sites has people wondering: Who did it?

No one has claimed responsibility yet, says CNN. That hasn’t stopped the conspiracy theories from flying that Russia could be behind the attack or even that the United States perpetrated it in a “false flag” attack to blame Russia. However, there are other theories. One site says that the hack might have been perpetrated by PoodleCorp, a shadowy group of hackers that previously claimed responsibility for crashing Pokemon Go. PoodleCorp had tweeted a cryptic message about October 21 in September:

Later in the day, though, Cybersecurity firm Flashpoint traced Friday’s widespread internet outage to the Internet of Things, according to cybersecurity expert Brian Krebs. Read more about that here.

Flashpoint is now reporting that the attack on Dyn today is in fact being launched by a Mirai-based IoT botnet — briankrebs (@briankrebs) October 21, 2016

WikiLeaks implied the hack was by its supporters.

Mr. Assange is still alive and WikiLeaks is still publishing. We ask supporters to stop taking down the US internet. You proved your point. pic.twitter.com/XVch196xyL — WikiLeaks (@wikileaks) October 21, 2016

Poodlecorp has gotten political at times, retweeting this in July:

Others said Poodlecorp and a hacking group called Lizard Squad might have banded together.

Amazon, Twitter, Netflix, and Spotify were just some of the prominent Internet sites shut down due to the DDoS attack, said CNBC. According to CNN, a DDoS attack “is an attempt to flood a website with so much traffic that it impairs normal service.”

The Internet false flag conspiracy theories – for which there is no proof – stem from news stories that the U.S. government was planning to launch a cyber attack against Russia to embarrass the Kremlin. NBC News reported October 14 that U.S. Intelligence officials told the network “The Obama administration is contemplating an unprecedented cyber covert action against Russia in retaliation for alleged Russian interference in the American presidential election.” The goal was to embarrass Putin and the Kremlin, said NBC.

Some Internet conspiracy theorists have extrapolated that information into the theory that the U.S. would stage the attack to pin the blame on Russia. Of course, there is no proof for that, and it’s just one of the wilder theories to emerge in the wake of the cyber attack.

What if the DDoS attack is being carried out by Obama as a false flag to blame #Russia and #Putin?? #FalseFlag #CyberWar #WW3 — H8 Hillary Follow Me (@brad_studio) October 21, 2016

And they love DDoS attacks. First act of cyberwar was Russia hitting the hell out Estonia in 2007. 5/ — Paul Szoldra (@PaulSzoldra) October 21, 2016

Exactly, @POTUS admin targeted Social Media w/ DDoS to get maximum "I'm so scared of the Russians" coverage, false flag https://t.co/sTn9EyObJm — MicroSpookyLeaks™ (@WDFx2EU7) October 21, 2016

Time Magazine says Homeland Security is involved in the investigation into the October 21 attack that disabled some of the most prominent sites on the Internet. The “U.S. Department of Homeland Security said the agency was ‘investigating all potential causes,'” Time said, adding that there were at least two separate attacks on October 21.

Many prominent sites crashed in the northeast of the United States in particular.

Various agencies in the United States have pointed the finger at Russia for the series of hacks, WikiLeaks and otherwise, into the emails of the Democratic National Committee and Democratic nominee Hillary Clinton’s campaign chairman, John Podesta. Clinton’s campaign has compared those attacks to a modern-day Watergate and attempted to attach Republican nominee Donald Trump to Russia and its leader, Vladimir Putin. Trump has responded that he doesn’t know Putin.

The Internet traffic company Dyn said on October 21 that it was “monitoring and mitigating a DDoS attack against our Dyn Managed (Domain Name System) infrastructure,” according to CNBC.

DDos attacks have been attributed to Russian hackers in the past. According to Group IB, a global security company, a Russian man was sentenced to probation after being convicted for Distributed Denial of Service (DDoS) attacks previously. The investigation ignited after an attack on a large financial corporation that owns several banks, says Group IB.