Sheriff's investigators are working to determine the cause of this morning's accident that killed a bicyclist in South Sacramento. 

The 59 year old man was riding along Stockton Boulevard near Elsie Avenue when he inexplicably turned in front of on-coming traffic around 6:30 a.m. 

The man was struck by an SUV and sustained major injuries after he was thrown off his bike and later died at the hospital.  The driver says he was unable to stop in time, and at this point, is not facing any charges.