As mentioned here, there is a trending twitter theme about the temper tantrum a Republican said Mitt Romney threw at the recent Univision taping.  Here is the Buzzfeed snippet.

Romney took issue with the anchors beginning the broadcast that way, said Salinas, and he refused to go on stage until they re-taped the introduction. (One Republican present at the taping said Romney "threw a tantrum.")
Five years ago Romney got caught in a lie by Glen Johnson of AP and angrily approached Johnson after the presser was over.  As Keith Olbermann noted later, Johnson was completely correct about the fact that Romney was telling a bold-faced lie.  Eric Fernstrom tried to end the presser abruptly and afterward accused Johnson of being unprofessional.  Yes, pointing it out when Romney tells a lie is... "unprofessional."  The embed code of that video has been disabled by request (wonder whose request that was?) but here is the link.  Note the anger on Romney's face when challenging Johnson.

More below the squiggly orange fold.

As I wrote earlier here, Mitt Romney lost his cool multiple times during the time he was in charge of the 2002 Winter Olympics. There was one incident where he blew up at a teenager charged with directing traffic:

Romney found himself stuck in a huge traffic backup on the road to the men’s downhill ski area, because some buses had not received the proper security-clearance placards and were being prevented from proceeding. Romney, who had organized the Salt Lake Olympics, jumped out to take charge. He started directing traffic, over the objections of a sheriff’s deputy, Kodi Taggart; she later filed a report on Romney’s interference. And he lit into an 18-year-old volunteering as a security officer, Shaun Knopp. Knopp told reporters that Romney had asked “who the fuck” he was and “what the fuck” he was doing and had then told him, “We got the Olympics going on, and we don’t need this shit going on.” Romney denied this at the time, saying he had not used such language since high school. “I would not, have not, and never would use the f-word,” he said. The worst word he used with Knopp, he said, was “H-E double hockey sticks.”


In the days after the incident, the state’s top law enforcement official decided against an investigation. But the officer in charge of security at the downhill site, Weber County Sheriff’s Office Captain Terry Shaw, said a police sergeant from Colorado working under his command had corroborated Knopp’s account, and Shaw demanded an apology from Romney.

This incident put Romney at odds with those in public safety positions:

Police were angered that Romney denied shouting the expletive and were further miffed when Romney later offered a partial apology to a sheriff's captain but not to Knopp.

''There were a lot of people in public safety who were extremely angry,'' said Peter Dawson, a lawyer today who served as an intern in a communications center at the time. ''The general consensus was, 'I hope he doesn't need any help from us because we aren't going to respond very quickly.'.''

Romney also had "clashes" with others while at Salt Lake, times when he seemed more menacing, and times that bring to memory previous stories like his attack of a fellow student.
Romney tolerated little dissent from trustees who aggressively questioned his decisions. While his many admirers in Salt Lake City viewed him as pristine, amiable, and self-effacing, he developed an alternate image among a group of dissenters: petty, vindictive, and self-aggrandizing.

His chief foe was Ken Bullock - no relation to Romney's friend and COO Fraser Bullock. Ken Bullock served on the organizing committee and also was executive director of the Utah League of Cities and Towns.

Garff, the organizing committee chairman whose association with Romney went back to childhood, believed Romney inappropriately tried to silence Bullock.

''Mitt saw him as an agitator,'' Garff said, ''and I saw him as a watchdog who needed to be heard.''

Romney showed little sympathy for another trustee who criticized his performance. When Lillian Taylor, a small-business consultant, questioned why the committee continued to retain a pricey law firm that had acknowledged losing documents related to the scandal, Romney, who at the time said he had no problem with her raising the issue, sat silently while the board's attorney aggressively dismissed her complaint.

Yahoo News notes four other episodes, including a 1981 arrest for disorderly conduct:
In 1981, Romney was putting the family boat into Lake Cochituate, an hour outside of Boston, when a park officer told him he couldn't because the license looked painted over. If he launched, he'd face a $50 fine. "I was willing to pay the fine," Romney told The Boston Globe. But the officer returned as Romney put the boat in and, visibly angry at being ignored, handcuffed Mitt, who was "dripping wet in a bathing suit," and booked him for disorderly conduct. Romney contested the arrest in court, threatened to sue, and got the arrest dismissed and sealed.
The other three events mentioned in the Yahoo News article included Putting Rick Perry in a "Vulcan neck pinch," Sparring with party rockers LMFAO, and yelling at a radio host over his gay marriage record.

There is also the attack on his classmate in 1965 when Romney was in prep school.  That story is here.

And those are just the stories we know about.

1:30 PM PT: updated to include LMFAO response at the time from youtube:

2:43 PM PT: Update 2 from AnnetteK in the comments.  More angry outbursts from Mitt:

5:52 PM PT: Gobacktotexas in the comments found a copy of the vidoe with Glen Johnson that is embeddable:

More video with him confronting an interviewer over Mormon belief discussion:

In a shouting match at Iowa State Fair:

Your Email has been sent.