It happened on September 3 just before 7:30 p.m. at a residence on the 400 block of South Jackson Street.
Officers were called to the scene to conduct a wellness check on an elderly woman.
At the home, police say they found 89-year-old Leonor Gonzalez-Ortiz dead inside.
Authorities later determined that her cause of death was due to an assault.
Through an investigation, 37-year-old Cynthia Viquez was identified as a suspect in connection with the assault.
She was taken into custody on September 4 and was initially charged with first-degree assault.
On September 16, authorities updated Viquez's charges to first-degree murder and providing a false statement to law enforcement.