There may be nothing that gets drivers' blood boiling more than a zipper merge, especially when they believe others are flouting proper traffic etiquette.

Tempers flared last week in a construction zone on Hwy. 10 in Coon Rapids, when the driver of a pickup truck appeared to purposely veer into the path of a sedan to prevent that driver from legally using the open lane to reach the merge point.

The vehicles collided. The impact briefly sent the sedan airborne before it crashed into the cable median barrier and came to rest in the left lane, its front end mangled.

No one was seriously hurt in the midday mishap in the westbound lanes near Round Lake Boulevard. As of Friday, no citations had been issued, and the crash remained under investigation, said Lt. Gordon Shank with the Minnesota State Patrol.

Nichole Morris, director of the University of Minnesota's HumanFirst Laboratory, saw the crash video first posted by Midwest Safety (@SafetyVid) on Twitter. She called the incident a disturbing act of road rage.

"This is a good example of traffic violence on the road," said Morris, who has spent years researching driver behavior. "It's mindful of what other drivers are capable of."

Morris said she has seen an uptick in aggressive driving in recent years.

"They don't think it will result in a crash," she said. "You think you can intimidate people to get them to behave in the way you want."

What MnDOT wants people approaching a construction zone to do is remain in their respective lanes until they reach the designated merge point. Then, like we learned in kindergarten, take turns and fall orderly in line, said agency spokesman Jake Loesch.

"Resist the urge to merge early," he said.

MnDOT in the early 2000s was the first in the nation to employ the zipper merge as a way to better manage traffic in work zones when a lane is closed. Using both lanes reduces backups and keeps traffic moving at a more consistent pace, Loesch said.

But the maneuver tends to go against human nature, he said.

"We don't want to be rude and cut in line or be cut off. Neither is happening in a zipper merge," Loesch said. "Letting one car in front of you won't slow you down."

MnDOT continues to look for ways to teach drivers why zipper merging is effective — and then get them to do it, Loesch said.

Meanwhile, the State Patrol saw its share of law-breaking motorists during last week's Operation Safe Driver. Troopers peering into vehicles from buses spotted motorists texting, emailing and watching videos during the three-day campaign to promote safe driving. Troopers issued more than 100 tickets.

"It's sad," said Capt. Jon Olsen. "There's a lack of responsibility that people should feel when driving a vehicle."

Olsen said the patrol spends a lot of effort on driver behavior, a focus that is increasingly crucial: This has been the deadliest summer in a decade, with 67 fatalities since Memorial Day.