Four bodies have been found in an area near Matamoros, Mexico where three Americans and one Mexican disappeared two weeks ago, The Associated Press reported.

Tamaulipas state investigator Raul Galindo Vira would not say if Erica, Alex and José ángel Alvarado Rivera had been identified. The Progreso, Texas, siblings, aged 26, 22 and 21, respectively, had traveled to Mexico to visit their father.

Witnesses last saw the Riveras, along with Erica's boyfriend, José Guadalupe Castañeda Benítez, 32, in the border town of some 3,000 that belongs to the Matamoros municipality, as they were taken away by armed men. Their abductors claimed to be part of Grupo Hercules, "a recently formed police security unit for Matamoros city officials," according to AP.

The siblings' mother, Raquel Alvarado, said their father told authorities Wednesday what the three were wearing at the time of their disappearance.

Meanwhile, a local paper, El Mañana de Matamoros said the parents identified three of the bodies as being their two sons and daughter.

"[They] made themselves available to the Coroner's Service, accompanied by from personnel from the U.S. Consulate and the FBI, and the victims were positively identified," the newspaper reported. "The body of the fourth victim was identified by his adoptive mother, Martha Hernández. The judicial authorities accepted the identifications of the victims' parents but stressed that DNA and scientific tests had yet to be performed. The State Prosecutor's Office confirmed that the bodies were burnt, with bullet wounds in the skulls and in an advanced state of decay."

In an earlier interview with AP, Hernández compared the situation to the Sept. 26 disappearance of 43 Guerrero college students at the hands of police. The fugitive mayor of Iguala, along with his wife and the city's police chief, have been implicated in that incident. Mexican President Enrique Peña Nieto had met the parents of the missing students in a closed-door meeting Wednesday.