Documents reveal new details in Nicole Montalvo death investigation

Deputies have released hundreds of pages of evidence in the case involving a St. Cloud mother who was brutally murdered and found buried in two different spots.

According to the documents, authorities found Nicole Montalvo's human remains buried two to five feet into the ground. They say the remains were of human organs that appeared to be cut with a cutting device and that the size of the burial was consistent with an excavator type of machinery being used. 

The documents detail that investigators made contact with Rental Wolrd, which rents out excavators. They were able to track an excavator to the property with a GPS system. 

According to the documents, Nicole Montalvo's estranged husband Christopher Otero-Rivera was wearing an ankle monitoring device, which showed him moving around the area where the human remains were found. 

A woman who was renting a room from the Riveras also told investigators she saw both Angel Rivera and Christopher Otero-Rivera using the excavator in the backyard and wouldn't let Nicole Montalvo's son join them. She told investigators that it was odd because the boy usually goes outside to be with his dad and grandfather.

Also included in the documents were letters that Angel Rivera wrote to his wife from jail. In the letters,  he writes that "The truth will come out and I will be home soon." He tells her he wants to take her on a cruise when he gets out of jail, telling her not to be afraid and that "we have done nothing wrong." 

Angel Rivera bonded out of Osceola County Jail Monday night.  Otero-Rivera is still locked up in Osceola County on a probation violation.