The number of shootings on U.S. interstates is up across the country and a big reason for this is aggressive driving. 

Even with more attention coming to this issue, it isn’t an easy fix according to the police.  

"You have the recipe for some real, real challenges," said Chris Loftis with Washington State Patrol. 

Washington State Patrol is seeing more shootings on highways - and they’re hard to prevent.  

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"Highways are dangerous enough without anything like this," Loftis said. "It makes it tougher to patrol and respond. And then it makes it tougher to investigate."

 Law enforcement attribute many of these shootings to aggressive driving and the reaction from surrounding drivers. 

"When you have situations where peoples’ behavior is changing about how they’re operating their vehicles," Loftis said. "And then peoples’ behavior changing in how they respond to aggressiveness. You overlay that with more people, more cars." 

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Over the last year, areas in Washington State, California, Wisconsin, Indiana, Pennsylvania and Florida have reported an increase in highway shootings. 

"The numbers are just too high," said David Reich with the National Road Safety Foundation.   

The best advice for drivers is to try to drive carefully and avoid aggressive drivers. 

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"Any time, if someone is driving aggressively, just try to stay away from them," Reich said. "It’s human nature to want to curse the guy out or do something to retaliate. But it’s not worth it." 

Washington State Patrol is fighting back with more officers on the road.  

"We’ve definitely put in more emphasis patrols and focused patrol units in certain parts," Loftis said. "Especially since we’re seeing so much."  

A shortage of police officers has also made it tougher to crack down on these shootings.