An image of former presidential candidate Hillary Clinton reading a newspaper has sent the internet into a frenzy.

However, the USA Today story Clinton was intently staring at was no ordinary news article, but one that many believe contained a comic sense of irony.

It contained details that US Vice President Mike Pence used a personal email address for sensitive security issues while governor of Indiana. And that his email account had been hacked.

Clinton's use of a private email server dogged the entirety of her presidential campaign with her counterpart President Donald Trump – then the Republican candidate – repeatedly calling for her to be locked up over the alleged wrongdoing.

The email controversy caused so much chatter that during the Democratic presidential debates, Vermont Senator Bernie Sanders quipped: "The American people are sick and tired about hearing about your damn emails."

The scandal also arguably lost Clinton the presidential race after the FBI's Director James Comey said the agency was reopening its investigation into the affair, days before the 2016 election, only for nothing to come of the probe.

Clinton was spotted staring at the newspaper with the headline, "Pence used personal email in office", as she travelled from Logan Airport in Boston to LaGuardia in New York on Friday (3 March).

It was captured by Caitilin Quigley, 32, who told the Huffington Post she took the picture after she believed it was "too good not to share".

The picture has since been shared on Facebook and Twitter thousands of times.

Pence's use of an AOL email account, which contained sensitive material on terrorism responses and the arrest of a number of men on terror-related charges, was first reported by the Indianapolis Star on Thursday.

Responding to reports, Pence said his use of a personal email was in compliance with Indiana law and that there was "no comparison" between what he and what Clinton did.