This is a weekly series that profiles America's most wanted criminals.

Two days before she was to stand trial on charges she murdered her newborn daughter, Alicia Leonor Banuelos took a bad situation and made it much worse.

The then-31-year-old resident alien from Mexico had lost custody of her eldest daughter, Lyric Garcia, in 1997, when police charged her with the first-degree murder of her other daughter — an infant they said Banuelos left to drown in a toilet after giving birth.

Banuelos arrived at her sister's house on Oct. 10, 1999, very upset over a meeting with her lawyer, according to a federal affidavit. Another sister suggested that she, Banuelos and Lyric spend their supervised visit at a suburban Chicago mall.

It was there, police said, that Banuelos snatched 4-year-old Lyric and never looked back. For nearly nine years, she has been on the run, evading murder and kidnapping charges in Illinois.

Her trouble began, investigators said, on April 29, 1997. According to the Palantine, Ill., Police Department report, Banuelos returned home from her overnight job at a grill factory. After sleeping into the early afternoon, she awoke and delivered her second child in the bathroom.

Police said Banuelos gave birth on the toilet in her home in Palantine and left her newborn daughter in the bowl for an indeterminate amount of time. An autopsy concluded the infant died by drowning.

"She delivered the baby and killed it," FBI Special Agent Ross Rice told FOXNews.com.

Banuelos told police that she had suspected she was pregnant but was in denial because her husband, Raul Garcia, had left her four months earlier. She may have joked about the pregnancy once or twice with a sister. She gained weight, she told police, but never sought prenatal care.

Palantine officials charged her with first-degree murder. Lyric, her toddler with Garcia, was placed in her sister's custody while Banuelos awaited trial. She had monthly supervised visits with the child as she prepared for the trial. Police said on that autumn day in 1999, she told her sister that she was taking Lyric to the mall's restroom. She never returned.

In the days after she fled, Banuelos contacted a boyfriend, according to a federal criminal complaint. That man told police that he believed she was either in El Paso, Texas, with another sister — or in Mexico.

A second call to the boyfriend was traced to a hotel in Zacatecas, Mexico, where Banuelos is believed to have friends.

"The family has been uncooperative," Rice said.

Banuelos is described as a 5-foot-6, Hispanic, 40 years old, with brown hair and brown eyes, weighing approximately 138 pounds. She is a Mexican national who has been known to use the aliases Leonor Banuelos, Alicia Banuelos, Leonor Alicia Banuelos, Alicia Banuelos-Flores and Alicia-Leonor Banuellos.

Investigators say her status on the FBI's most wanted list is because of the cruelty of her crime.

"There’s no indication that she’s in possession of, or ever used, a weapon," Rice said. "I don’t think she has a criminal history besides this, but obviously, if you can kill a newborn and abduct a 4-year-old, I guess you’d have to be considered at least dangerous to the 4-year-old’s safety."

There have been no sightings of Banuelos since 1999, and officials said they do not know if Lyric, who would now be around 13, is still alive.

Anyone with information as to Banuelos' whereabouts should call the FBI in Chicago at 312-421-6700.

Click here for more coverage and to see Banuelos' FBI poster profile.