An arsonist with an affection for haystacks may have struck for the third time in one day Tuesday, igniting hay inside a barn on 300 West near 9600 South.

A Salt Lake County deputy sheriff was driving on I-15 when he spotted smoke coming from the barn about 11:30 p.m. The deputy had been on the lookout for fires along the I-15 corridor because of a string of recent arson fires in Salt Lake and Utah counties, said Sandy fire Battalion Chief Gary Childs.Childs said the hay had been smoldering for some time when firefighters arrived, but it never turned into much of a fire, unlike a 1:34 a.m. fire in Riverton that took about 40 firefighters more than five hours to douse and clean up.

"It wasn't a big ordeal," he said. Damage was estimated at $100. "We spent more time looking at it than we did putting it out."

Investigators believe that more than a dozen fires in the two counties may be the work of an arsonist who possibly drives a two-tone Chevrolet pickup truck, 1973 or newer, that has a loud exhaust system.