The incident happened in Wasco, a city just north of Bakersfield.
A graphic video going viral on social media shows the man who authorities say took the body part from the scene. In the footage, he is seen carrying a severed lower leg and foot down a street in the area.
At one point, the man bent over and appeared to sniff the apparent body part.
Kern County sheriff's deputies quickly swarmed the area and arrested that man. They are now studying that video for what could be numerous criminal charges.