(CNN) -- For five years, they pursued her, always one step behind as she used aliases and altered her appearance to elude them.
But Janet Killough Barreto's luck ran out at a shopping mall in Portland, Oregon, where the U.S. Marshals Service caught up with her -- the lone female fugitive in their 15 Most Wanted list.
"The crimes they are alleged to have committed are nothing short of horrendous and despicable," Union County, Mississippi, Sheriff Jimmy Edwards said, about Barreto and her husband. His department aided in the search because her alleged crimes took place in his jurisdiction.
"Now it is time to let justice be served."
Abuse leads to death
Barreto, 43, and her husband, Ramon, allegedly traveled to Guatemala on multiple occasions in 2005 and 2006 to purchase children from a local adoption agency. Authorities say the children were brought back to the United States and were malnourished, physically abused, and forced to sleep on beds with plywood bottoms.
"The children were purportedly often punished with beatings and on various occasions duct-taped to their beds, punched in the stomach, and forced to endure having their heads submerged under water," the Marshals Service said.
In 2008, the abuse allegedly led to the death one of their adopted children, a 2-year-old girl.
Barreto was arrested in May of that year for child abuse, neglect, and manslaughter. She was released six months later on bond.
On the run
In March 2009, Barreto was arrested again for tampering with a witness and later released on bond. Two months later, she never appeared in court to face the charges against her, authorities said.
The Union County Sheriff's Office began searching, aided by the U.S. Marshals when Barreto was added to their "15 Most Wanted" list in June 2013. Authorities asked the public for any information leading to Barreto, offering a $25,000 reward.
A "Wanted" poster distributed by the Marshals Service said Barreto was known to change her appearance using wigs. It also said Barreto would evade law enforcement through the use of several aliases, fleeing before her true identity was discovered.
The call came in on Monday.
According to authorities, the five-year investigation gained considerable momentum when a "concerned citizen" called the U.S. Marshals task force in Oxford, Mississippi, with information that placed Barreto in either Oregon or Washington. The caller also told authorities that the Barretos might have a small child with them.
The investigation moved swiftly.
Less than 24 hours after that initial tip, a lead about a possible location sent agents to Oregon.
They cornered Barreto and her husband late Tuesday afternoon at the Jantzen Beach Center, a shopping mall in Portland.
At first, the Barretos refused to identify themselves, but the husband was identified on the spot when his fingerprints were verified digitally.
Though Barreto continued to be uncooperative, her identity was revealed once she was fingerprinted at a local jail.
"Janet Barreto is a malicious individual. Through her alleged crimes, Barreto demonstrated a blatant disregard and lack of respect for life other than her own," said U.S. Marshals Service Director Stacia Hylton.
The infant found with the Barretos during their arrest was placed with child protective services, authorities said.
Six years after the death of their daughter, it's uncertain what the Barretos will face upon their return.
Both are currently being held at the Multnomah County Detention Center in Portland, awaiting extradition to Mississippi, authorities said.
It is unknown whether either has retained an attorney.