FILER, Idaho (KLIX) – Smoke hampered visibility earlier today near Filer.

Firefighters were up all night fighting a blaze that ignited in a haystack, according to Filer Fire & Rescue. The agency said on its Facebook page that the fire was near U.S. Highway 30 and smoke was impacting visibility.

Four fire trucks were still on scene this afternoon, said Lori Stewart, spokeswoman with the Twin Falls County Sheriff’s Office. The fire, which was reported at 1:31 a.m., is near milepost 207.

Stewart said cause of the blaze has not yet been determined.

“Please be cautious when driving in the area,” the Filer Fire & Rescue post reads. “Crews will be on scene for several more hours.”