Eric Trump proudly posted a photo of his vote for his father, Donald Trump, on social media. 

There is only one problem it is illegal in the state of New York to share a picture of an official election ballot. 

"It is an incredible honour to vote for my father!" Mr Trump wrote in the now-deleted tweet. "He will do such a great job for the USA!"

Soon afterward, though, the Election Day tweet mysteriously disappeared, but not before being captured for posterity by Twitter users.

The Trump campaign didn't immediately respond to a request for comment.

The current sanction for a ballot selfie in New York is a $1,000 fine or up to a year in jail.