Authorities in Nevada are warning drivers to be cautious after Mormon cricket “sludge” caused several crashes over the weekend.

The icky combination of mashed Mormon crickets run over by cars and recent rain created a slippery muck over roads and led to two crashes involving three semi-trucks on Interstate 80, the Eureka County Sheriff’s Office. No serious injuries were reported from the crashes, a spokesperson from the sheriff’s office said.

The office, as well as fire, emergency services and Nevada State Police responded to the multiple crashes Saturday and warned vehicles to slow down as the unsavory mixture made “roadways EXTREMELY slick and unpredictable for stopping distance.”

The giant, cannibalistic bugs, which don’t directly harm humans, made headlines last year after swarming towns across the state.

Nevada’s state entomologist Jeff Knight told NBC News last year that outbreaks of Mormon crickets typically last four to six years and eventually drop off due to natural predators. Before 2019, Nevada went more than a decade without seeing the crickets.

Their eggs remain in the soil until a drought cycle triggers them to finally hatch, he said.

The crickets have already been a menace in some northern Nevada communities. They were seen inundating Jesse Hall Elementary School in Sparks, prompting the cancellation of some outdoor activities, including recess and physical education classes earlier this month, NBC affiliate KRNV of Reno reported.

Residents were being encouraged to report sightings of the creatures to aid in treatment efforts.

The critters are a “common occurrence” throughout northern Nevada and other Western states, and their populations can reach levels that “pose a risk to agriculture and public safety on roadways,” according to the state’s Department of Agriculture.

This article was originally published on NBCNews.com