DES MOINES — Five years ago today, a deer died and a social media legend was born.

Well, we assume the deer died.

It was five years ago today — Oct. 25, 2012 — that U.S. Sen. Chuck Grassley’s vehicle hit a deer on an eastern Iowa road, presumably killing the animal.

Grassley tweeted about the experience, and the tweet’s closing phrase, “Assume deer dead,” became a Twitter legend, still referenced by Twitter users.

Grassley, 84, is one of Congress’ more well-known Twitter users, with his unfiltered, 140-character messages, often delivered in his unique shorthand — Grassley composes his tweets, not a staffer — about both politics and items of personal interest, like University of Northern Iowa athletics or his laments about what he thinks is a lack of historical content on The History Channel.

Of the more than 6,000 times Grassley has tweeted, however, one stands out.

According to Grassley, on Oct. 25, 2012, he was being driven through eastern Iowa — he cannot recall from or to where — by Fred Schuster, the regional director for Grassley’s office in Cedar Rapids, in Schuster’s Prius.

They were traveling on Highway 136 south of Dyersville when something — they couldn’t see what — struck the car. They did not immediately know the extent of the damage, but could tell the fender was rubbing on the tires, so they pulled over.

“This was a Prius. Their body is made of tin foil,” Grassley joked during a brief phone interview this week.

The inspection made it clear: they had struck a deer. And although they could not see the animal, Grassley was sure what happened.

“I just had to presume the deer was dead, because I never did see the deer,” Grassley said.

Grassley thought word of the incident might spread, so he took the proactive step of tweeting it out. He said he primarily was thinking about his staff when at 8:31 p.m. he tweeted this:

“Fred and I hit a deer on hiway 136 south of Dyersville. After I pulled fender rubbing on tire we continued to farm. Assume deer dead”

That last phrase, “Assume deer dead,” caught the attention and tickled the funny bones of thousands of Twitter users. Within a week it had been retweeted more than 1,000 times, and born was a meme that lasts to this day.

It wasn’t Grassley’s most shared tweet. With more than 3,100 retweets, that’s well off the pace of many of Grassley’s others, including another well-known tweet in which he said he was visiting a suburban Des Moines Dairy Queen to enjoy some “u know what,” meaning ice cream. That has been retweeted more than 6,700 times.

It’s the staying power of Grassley’s “Assume deer dead” tweet that makes it stand out. Twitter users who follow Grassley and know his Twitter style still make reference to the tweet five years later.

For example, in May when Grassley called for an investigation into the Chinese promotion of a deal for the family of President Donald Trump’s son-in-law, Twitter user Heidi Moore tweeted a link to the story and added her caption, “Assume deal dead.”

The incident that led to Grassley’s tweet was not unlikely. Grassley spends a lot of time on Iowa’s roads — he is famous for traveling to each of Iowa’s 99 counties every year — and Iowa in 2016 had the fourth-best odds for a vehicle to hit a large animal, including deer, according to State Farm Insurance.

The tweet’s longevity has surprised Grassley, and he has joined the running gag, making references a handful of times over the years since the original tweet. In a January 2015 tweet he said Schuster had again struck a deer, this time without Grassley in the car.

Even this week while talking about that viral tweet, Grassley relayed a story about recently being in the car with Fred driving back from the final of his 99 county meetings and just missing hitting a deer.

“This was daylight. I think it was real early in the morning. We actually saw a deer, and we were able to slow down and miss it,” Grassley said. “I told Fred, ‘If you hit that deer, I’d be able to get 10,000 more tweet followers.”