SACRAMENTO (CBS SF) -- Officials in Sacramento are raising the alarm after finding more decapitated animals along the city's light rail tracks, bringing the total number to more than a dozen since January.

On Saturday, a light rail operator saw someone get out of a white van and place the animals by the railroad tracks.

Gina Knepp, who manages the Front Street Animal Shelter and Animal control for the City of Sacramento says there was a young goat, or a pygmy goat with its head lying next to its body.  There was also a bag of dead chickens, a headless rat and decapitated catfish.

"There is absolutely a proven nexus between people who intentionally harm and mutilate animals, almost like it's a gateway drug, and then move on to harming people.  Many many many serial killers started that way," Knepp said.

The grisly findings add to a number of decapitated goats, birds a turtle and even cows in parks, remote areas and along light rail tracks in the region in recent months.