Some of the bones and a skull found Sunday in a Pasadena backyard are human, the Los Angeles Coroner's Office has confirmed.

A man who left the house Monday said that his sister's family had found the bones for sale on eBay, and that she purchased them for religious reasons. The man identified himself only as Jose, declining to give his last name.

Police said they were pursuing a trespasser when they spotted bones atop the outdoor altar. Steer horns and other animal bones were visible, along with the human bones, candles and incense. 

"The religious aspect of the case is not our focus -- it's the bones," said Pasadena Police Lt. Ed Calatayud. 

Human skulls indeed are listed for sale on eBay.  On Monday, for example, one described as suitable for dental study was listed at $710.

Jose said his sister practices Palo Mayombe, an offshoot of Santeria.

'The Saint of Death'
Studying images of the statues on the altar, an expert on Latin American folk religions saw different symbolism.

"What caught my eye was that the backyard altar was obviously primarily an altar to Santa Muerte, the Saint of Death ... whose cult has been mushrooming both in the United States and Mexico over the past decade," said R. Andrew Chesnut, professor of religious studies and holder of the Bishop Sullivan Chair at Virginia Commonwealth University. 

"What it really is, is a fusion of medieval Catholicism and native Mexican folk religion,” said Chesnut, the author of "Devoted to Death:  Santa Muerte, the Skeleton Saint."

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Santa Muerte has continued to grow, despite condemnation from the Catholic Church and from the federal government of Mexico, Chesnut said. 

Santa Muerta is distinct from Santeria, but creation of personal altars is a characteristic among followers of both, and in some cases altars are adorned with bones, both animal and human.

"The bones themselves are often believed to have special powers,” he said.

The coroner's office took custody of the bones and skull discovered in the 800 block of North Oakland Avenue. 

At this point there is no indication of any crime, police said.  But the coroner will attempt to determine their origin.