OSCEOLA COUNTY, Fla. – A third arrest has been made in connection with the death of a missing woman in Osceola County.
Deputies with the Osceola County Sheriff's Office said Wanda Nereida Rivera, 59, the mother-in-law of Nicole Montalvo, was arrested Friday.
Rivera's arrest comes one week after deputies said Montalvo's remains were found on a property in St. Cloud that belongs to Rivera and her family.
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After the remains were identified, Montalvo's estranged husband and Rivera's son, 31-year-old Christopher Otero-Rivera, was charged with first-degree murder. Rivera's husband and Otero-Rivera's father, Angel Luis Rivera, 63, is also facing murder charges.
Montalvo's remains were found during an extensive search of the Riveras' property on Hixon Avenue after Montalvo was reported missing, deputies said. They were not immediately able to be identified due to their condition, deputies said.
Additional remains were found at another location and have not been identified as Montalvo's yet, but deputies said they don't have a reason to believe they wouldn't belong to her.
During a news conference held Friday, Osceola County Sheriff Russ Gibson confirmed that Montalvo's body was dismembered.
"Probably the most gruesome murder scene that I have seen in my 32 years," Gibson said.
Montalvo was last seen alive on Oct. 21 when she dropped her son off at the home where Otero-Rivera lives with his parents, deputies said. She was reported missing after she failed to pick her child up from school.
Friends and family said her phone was off, she wasn't responding to social media messages, and she didn't show up to work, all of which was unusual for Montalvo.
Authorities have not released information about how Montalvo died or what evidence led them to charge both men with first-degree murder.
Deputies said Friday that a warrant for Rivera's arrest was obtained after investigators determined that statements she made at the beginning of the investigation were false.
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Rivera faces charges of tampering with evidence and providing false statements during the commission of a felony crime, the sheriff said. Her bail has been set at $100,000, deputies said.
Rivera is expected to appear before a judge Saturday. Deputies said she has no prior criminal history.
Gibson, who said in a news conference last week that more people are believed to be have played a role in Montalvo's death, said on Friday that investigators still believe at least one additional person was involved. Gibson encouraged them to come forward.