Los Angeles Police Department / Instagram @cindyanasantangelo Composite

A California woman accused of killing "ER" star Cindyana Santangelo with a silicone butt injection has been convicted of murder ... a year and a half after being convicted in the death of another woman by the same method.

Libby Adame -- nicknamed "The Butt Lady" -- has been found guilty of second-degree murder and practicing medicine without a license in connection with Cindyana's death . Los Angeles Police Department

Santangelo died March 24 this year ... investigators said results from her autopsy showed she suffered an embolism from a silicone injection that had been administered earlier that day.

Libby Adame is set to be sentenced on November 5, the L.A. Times reports .

This isn't Adame's first r

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