The daughter of an American citizen kidnaped in Mexico over a month ago is holding out hope her mother is still alive after hearing her voice on a ransom call.

Zonia Lopez's 63-year-old mother was last seen watering her plants at her Pueblo Nuevo home in Mexico’s Colima state on Feb. 9 when masked strangers arrived at the property in a white van, picked her up and took her with them after a brief altercation.

Her family has since received ransom calls requesting massive sums of money for Maria del Carmen Lopez's return.

AMERICAN CITIZEN KIDNAPPED IN MEXICO WAS SEEN BEING FORCED INTO VAN, DAUGHTER SAYS

Zonia Lopez Fox & Friends First

Zonia Lopez says her mother was kidnaped from her small-town residence in Mexico. (Fox & Friends First/Screengrab)

"We're a normal working family. We don't have that type of money," Lopez said Wednesday on "Fox & Friends First."

Though her mother's voice was absent from one call demanding money, Lopez said she heard her on a separate recording, pleading for her family to meet her kidnapers' demands. "We did hear her voice – there was a recording – in one of the phone calls where she is pleading for us to pay this money and that her life depends on it," Lopez explained.

She told anchors Todd Piro and Ashley Strohmier she believes Maria, a retiree who moved to Mexico, was targeted for being a U.S. citizen.

AMERICAN CITIZEN ‘KIDNAPPED FROM HER RESIDENCE’ IN MEXICO, FBI SAYS 

Missing American Maria del Carmen Lopez

Maria del Carmen Lopez is a U.S. citizen who "was kidnapped from her residence in Pueblo Nuevo, Colima, Mexico, on February 9, 2023," the FBI says. (FBI)

"I think it's very common now that a lot of families go back to Mexico and retire there. People there probably assume they have more than them, but the reality is they don't."

Maria's disappearance follows a U.S. State Department warning last October for Americans to stay away from Mexico’s Colima state "due to crime and kidnapping."

Leading up to the event, however, her daughter said there were never any "red flags" that made her mother feel threatened, and she felt so comfortable with the area that she left the front gate open outside her home.

MEXICO MEDICAL TOURISM BOOMS AS AMERICANS RISK LIVES FOR SURGERIES 

Maria del Carmen Lopez image

The FBI's Los Angeles Office says Lopez has ties to southern California. (FBI)

Maria also never "expressed" any sense of danger, including being stalked or followed by someone, Lopez said.

"It's devastating. It really feels like we are just living the same day over and over again… It's really hard for me to just keep counting [the days]. We're hanging on for just one more day, and it's going on for 42 days today," she added, her voice beginning to break. 

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Lopez said she is still holding out hope her mother is alive, but she has received little information from Mexican authorities.

Maria is described by the FBI as being around 5 feet, 2 inches and weighing 160 pounds, with blonde hair and brown eyes. Her eyeliner, they added, is "permanent/tattooed." 

A $20,000 reward is being offered to anyone with information leading to her whereabouts. 

Fox News' Greg Norman contributed to this report.