FRESNO, Calif. (KSEE/KGPE) — A 33-year-old bicyclist has died after a crash involving a semi-truck early Monday morning, according to the California Highway Patrol officers.

Around 4:00 a.m., officers say they responded to the area of Jensen and De Wolf avenues after a collision was reported.

According to investigators, a semi-truck was traveling east on Jensen near DeWolf, and for reasons yet to be determined, a man from Sanger was riding his bike veered to the left, directly in the path of the approaching semi-truck. The front of the semi-truck hit the rear of the bicycle causing the rider to be ejected onto the roadway where he died.

Authorities say the bicyclist was not wearing a helmet and the driver of the semi-truck has been cooperative with the investigation.