SPRINGVILLE — A human-caused fire estimated between 75 and 100 acres put out heavy smoke and flames close to the border of Provo and Springville in Utah County, fire officials said Thursday.

The blaze, dubbed the Milrace Fire, is burning near the 1400 North exit on I-15 in Springville, according to Utah Fire Info.

The fire is burning in marshy terrain and phragmites, which is making conditions difficult for fire crews to access it. No structures or homes are threatened at this time.

Photos show a thick cloud of black smoke billowing over the southbound lanes of I-15, and flames visibly burning in vegetation on the west side of the freeway.

A brush fire burning in brush near the border of Provo and Springville on Thursday. (Photo: Brooke Bancroft)

Smoke from the fire is impacting visibility on I-15. Officials initially warned that a possible wind shift could impact the Provo Airport but later said that the winds have begun to decease, and crews have been able to get a better handle on the fire.

Just before 8:30 p.m., officials said the cooler evening temperatures and higher humidity reduced fire activity. People in the area may see smoke and occasional flames throughout the night, but crews plan to monitor the blaze and will reassess Friday morning, Utah Fire Info said.

The fire is under investigation.

Correction:Utah Fire Info initially reported the name of the fire as the Miracle Fire but later called it the Milrace Fire.