An infamous killer on Utah's death row has died in prison.

The Utah Department of Corrections says Ron Lafferty died today of natural causes.

Lafferty and his brother, Dan, brutally killed their sister-in-law, Brenda, and her baby daughter, Erica, in 1985.

The men claimed they had been commanded by God to kill the victims.

Dan Lafferty is serving life in prison for the murders.

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