Anne Mae Demegillo, a 20-year-old college student, was indicted by a grand jury on Monday on charges of first-degree premeditated murder in connection with her newborn's death.

According to authorities, Demegillo is accused of allowing her newborn to drown in a toilet after giving birth. The Florida sheriff's office investigating the case reported that images of Casey Anthony were found on Demegillo's phone during their investigation.

The grand jury indictment represents a formal charging decision in the case, elevating the matter from initial accusations to formal criminal proceedings. First-degree premeditated murder charges indicate that prosecutors believe the killing was planned in advance.

Casey Anthony gained national attention in 2011 when she was acquitted of murdering her 2-year-old daughter Caylee Anthony in a highly publicized Florida trial. The discovery of Anthony-related images on Demegillo's phone has become part of the evidence in the current case.

The investigation into the newborn's death remains ongoing as the case proceeds through the legal system. Demegillo faces the most serious murder charge available under Florida law.