A woman on trial for murder admitted in a recorded interview with police that she had shot two men and fed their bodies to her pigs, the jury heard on Tuesday.

Susan Monica, a 66-year-old pig farmer and welder from southern Oregon, went on trial on Tuesday in Medford.

She has been charged with killing two handymen living on her 20-acre pig ranch in a small Jackson County community and dismembering the bodies.

Accused serial killer Susan Monica interrupts court in Medford, Oregon on Tuesday on the opening day of her trial for allegedly murdering two men, dismembering their bodies and feeding them to her pigs

Susan Monica, pictured left in court in January 2014, and right in an undated mugshot, has been accused of killing Robert Haney and Stephen Delicino a year apart at her pig farm and dismembering their bodies

Both victims were shot in the head and dismembered in what prosecutors allege were separate murders committed more than a year apart.

Monica appeared in court dressed in skirt, blouse and short wig.

In opening statements, defense lawyer Garren Pedemonte said Monica shot the first victim in self-defense, and the second as a kind of mercy killing.

Stephen Frank Delicino, 59, was shot by Monica in self-defense in summer 2012.

The defendant has claimed that she shot the second man, 56-year-old Robert Harry Haney, to put him out of his misery because she found her pigs already feeding on him, The Mail Tribune reported.

The second killing took place in September 2013.

Police searched her pig ranch last year after Monica was discovered using a food stamps card belonging to Haney, and found remains of the two men.