ULLIN – An investigation is underway after a semi caught fire on I-57 in Pulaski County Wednesday morning.

According to a release from the Pulaski County Sheriff’s Office, deputies responded to the northbound on-ramp at exit 18 around 3:46 a.m. where they found a semi and trailer on fire. The driver was uninjured and was outside of the vehicle when deputies arrived.

A crew from the Ullin Fire Department extinguished the fire shortly after arriving. The cause of the fire is currently unknown.