On Monday night, as people attempted to find information on the damage inflicted on the east coast of America by Hurricane Sandy, misinformation spread quickly online. Furthermore, the spread of such misinformation was abetted by journalists, who were once taught the importance of verifying every source. Rumors and misleading photos quickly overtook Twitter and are continuing to feature heavily on Facebook, as people share the most shocking – and occasionally untrue – stories about the powerful storm.

As millions across the East Coast lost power, many relied on social networks for updates on their situation, only for the most persistently shared untrue stories to be backed by reputable news organizations. Within hours, such rumors were debunked by other reporters who tried to verify the information. The organizations concerned, including Con Edison and the MTA, also used their social-media arms to dispel myths.

Con Edison

Reuters reported that 19 Con Edison workers were trapped inside a power station. The organization said on Twitter that the report was untrue and a Con Ed spokesman, Allan Drury, confirmed to the Guardian that the story was false. On Tuesday afternoon, Reuters' 12-hours-old story was still online.

"There was really nobody trapped in the building," Drury said. "There was some people that were helped out, but they probably could have got out on their own."

The complex Drury to which referred is located on East 13th Street, near FDR Drive. At around 8:30pm on Monday night an explosion at the facility knocked 250,000 customers out of service.

"We're not sure of the cause of the explosion," Drury said. "It could have been flooding from the incredible storm surge we had, it could've been debris flying into our equipment."

A video was shared on social media and by news organizations, including the Associated Press, that claimed to show the explosion happening. Drury said he did not know how the video was filmed and could not confirm its accuracy. He could not confirm reports on Twitter that said people were seeing the sky light up with other explosions.

As for an estimate of how long it would take to restore power to areas that had lost it, Drury said: "For our entire system, which is five boroughs of New York City and Westchester county, restoration will probably take at least a week."

MTA

The Wall Street Journal reported that Metropolitan Transit Authority chairman, Joe Lhota, had estimated that New York City subways would be closed for "at least a week". This was debunked by the MTA's verified Twitter account.

In a Tuesday-morning press conference, New York City mayor Michael Bloomberg said that public transportation would be down "until further notice", and estimated that a limited bus service could be restored by Tuesday afternoon and a full service restored as early as Wednesday.

Bloomberg later pinned a more specific number to subway and power restoration, saying that "if you had to guess", it could take three to four days (subway) and four to five days (power) before the services were restored. Seconds after the mayor's announcement, Twitter users, including journalists, shared both numbers. The MTA then reiterated on Twitter that there was no timetable for restoration.

New York governor Andrew Cuomo staged a press conference after Bloomberg's press conference had finished. He announced that a limited bus service would be restored at 5pm Tuesday, and that people would not have to pay any fare.

NYSE

A meteorologist told CNN's Piers Morgan that the trading floor of the New York Stock Exchange was under 3ft of water. The story lasted for several minutes, with Morgan asking experts about the implications the flooding could have on the economy. The program's financial correspondent, Ali Velshi, said: "This will have an influence worldwide on people's wealth."

Ten minutes later, CNN said the story may have been unconfirmed. On Twitter, journalists who had put in calls to the New York Stock Exchange confirmed that the story was wrong.

In the broadcast, CNN said that the National Weather Service had provided the information, but the organization denied in a statement that it was the source. CNN later issued a correction and said the information had come from a "chat bulletin board" that the meteorologist had mentioned briefly on air when Morgan later questioned the claim.

Before Hurricane Sandy made landfall, doctored photos of sharks in New York streets and outdated images of East Coast landmarks made the rounds. Twitter users debunked some of the more shocking photos quickly, revealing that images from the disaster film The Day After Tomorrow, stock photos and photoshopped images of the streets were being passed off as fact.

On Monday afternoon, the Guardian's Katie Rogers collected some of the most heavily circulated deceptive photos and put together a helpful guide on how to spot deceptive pictures and verify others. Alexis Madrigal of the Atlantic is also identifying fake and real photos purported to be from Hurricane Sandy.

Within hours of most such photos and rumors appearing on Twitter, most had been challenged and disproven. The same could not however be said for Facebook, where information is spread through networks instead of in a public forum.

Recovery efforts are now in effect, but rumors will continue to spread as people try to keep up to date. So exercise skepticism before sharing links online.