The decomposing body of actress Julia Marichal Martinez was found in a water tank at her Mexico City home, authorities said.
A murder investigation was opened after the 67-year-old actress's body was discovered on Friday, Federal District Attorney's Office said.
Marichal's relatives filed a missing person's report with the Center for Missing and Disappeared Persons, or CAPEA, but her body was found a few hours later at her residence.
Investigators "are conducting studies to determine the types of injuries present and how many days had passed since death", authorities said.
Marichal was the daughter of Cuban actress Esther Martinez Penate, who married Mexican writer Juan de la Cabada.
The late actress appeared in a dozen "telenovelas", or soap operas, including "Mundo de Juguete" (1974), and a number of films, such as "Las puertas del paraiso" (1971).
Marichal worked for several well-known directors, including Alejandro Jodorowsky and Ana Sokolov.