Hillary Clinton took to Twitter on Monday night to share her opinion on National Security Advisor Michael Flynn's resignation, suggesting there are 'real consequences of fake news'.

Clinton retweeted a post from longtime confidante Phillipe Reines on Monday night, where he suggested Flynn and his son, who spread the discredited 'Pizzagate' conspiracy theory on social media, get jobs at Domino's.

'Philippe's got his own way of saying things, but he has a point about the real consequences of fake news,' Clinton said in her tweet.

Reines had written, 'Dear Mike Flynn & Mike Flynn Jr., What goes around COMETS around. And given your pizza obsession...', with a link to Domino's Pizza's job site.

The social media posts came after Flynn stepped down from his position as National Security Advisor in the Trump administration just 24 days after the new president's inauguration.

Hillary Clinton retweeted a post from longtime confidante Phillipe Reines on Monday night after retired Army Lieutenant General Michael Flynn resigned from his position as National Security Advisor

Reines suggested in his tweet that Flynn and his son, who spread the discredited 'Pizzagate' conspiracy theory on social media, get jobs at Domino's

In her tweet on Monday night, Clinton suggested that there are 'real consequences of fake news'

In December, Flynn Jr tweeted about the Pizzagate conspiracy, which linked Clinton and her campaign chief to Comet Ping Pong pizza shop in Washington, DC.

The theory suggested that Clinton and John Podesta presided over a child-sex ring run out of the DC pizza parlor.

Police said a 28-year-old North Carolina man opened fire with a rifle inside the restaurant in December because he thought child sex-slaves were being held against their will in the basement.

No one was harmed but the man was arrested.

In his tweet, Flynn Jr did not endorse the conspiracy theory, but predicted that it wouldn't go away.

'Until #Pizzagate proven to be false, it'll remain a story. The left seems to forget #PodestaEmails and the many 'coincidences' tied to it,' he tweeted

Flynn Jr returned to Twitter on Monday after being absent for two weeks to send out a message about his father's resignation.

Michael Flynn (pictured with his son, Michael Flynn, Jr) stepped down from his position as National Security Advisor in the Trump administration just 24 days after the new president's inauguration

In his tweet from last year, Flynn Jr did not endorse the conspiracy theory, but predicted that it wouldn't go away

Flynn Jr returned to Twitter on Monday after being absent for two weeks to send out a message about his father's resignation. He later deleted the tweet

'The disinformation campaign against my father won #AmericaFirst #USA #Flynn #FlynnResignation,' he wrote.

Flynn Jr later deleted the tweet and retweeted a Daily Caller post about an op-ed titled: 'Why We Should All Support Michael Flynn Against A Plot To Weaken America.'

Retired Army Lieutenant General Flynn resigned on Monday after revelations he had discussed US sanctions on Russia with the Russian ambassador to the United States before Trump took office and misled Vice President Mike Pence about the conversations.

His stunning announcement, first reported by CNN, came just hours after sources close to the government revealed that the Justice Department had warned the new administration that his links with the Kremlin had put him in a compromising position and left him open to blackmail.

Flynn made numerous phone calls to the Russian Ambassador to the US before Trump took office, and later hinted he may have gone against diplomatic protocol by discussing the rollback of sanctions.

Retired general Keith Kellogg will take over as acting National Security Advisor.

Former CIA Director David Petraeus and US Navy Admiral Michelle Howard are among the names being touted as a replacement.