ST. CLOUD, Fla. — In an update Friday afternoon, Osceola County Sheriff Russ Gibson said Nicole Montalvo's mother-in-law was arrested for tampering with evidence and providing false statements when she was questioned by detectives.
Gibson said Wanda Rivera was arrested and placed on $100,000 bail.
"This is what this case is showing, that there are other people involved in this case still today," Gibson said.
[ Read: Deputies: Human remains identified as missing St. Cloud woman ]
"Our mission is the same; there is no rock that you can hide under to avoid being held responsible and accountable for the heinous actions that you have done. It is best for you to come forward," Gibson said.
[ Read: Husband, father-in-law charged with murder in St. Cloud woman's death ]
Gibson confirmed Sunday that Montalvo's remains were found last Friday on the property near where her estranged husband, Christopher Otero-Rivera, and her father-in-law, Angel Luis Rivera, live.
Gibson said Otero-Rivera and Rivera were charged with premeditated murder. Both were previously named persons of interest in the case and arrested on unrelated charges Oct. 25.
[ Read: 'Love should not hurt': Friends, family hold vigil for slain Osceola mother ]
Deputies had searched the property on Hixon Avenue since Montalvo was reported missing last Wednesday.
A vigil was held for Montalvo at Lakefront Park Monday.
Watch Rivera walk out of the Osceola County Sheriff's Office:
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