One of the FBI's most notorious fugitives wanted in connection with a 2016 North Carolina killing has been arrested in Mexico after nearly a decade on the run, ending a cross-border hunt that spanned continents and several law enforcement agencies.

Alejandro Rosales Castillo, 27, was detained in Pachuca in the central Mexican state of Hidalgo by Mexican authorities acting on a red notice and extradition order tied to U.S. murder and federal flight charges, according to Mexican security officials and the FBI. 

Castillo, who was born in Arizona but had been living outside the United States for more than nine years, remained in custody in Mexico City awaiting extradition to North Carolina.

Castillo had been a fixture on the FBI's Ten Most Wanted Fugitives list since October 2017, carrying a reward of up to $250,000 for information leading to his capture. 

U.S. and Mexican officials credited coordination between the FBI's Legal Attache Office in Mexico City, Mexico's Secretariat of Security and Citizen Protection and its Federal Prosecutor's Office, and INTERPOL for locating Castillo.

Federal and Mexican agencies said Castillo will be extradited to face justice in Charlotte for the 2016 fatal shooting of 23-year-old Truc Quan "Sandy" Ly Le of Charlotte, whose body was discovered in a wooded area of Cabarrus County, North Carolina, shortly after she disappeared.

Prosecutors allege that Castillo, a former co-worker of Le's, fled the country shortly after her death.

Authorities have described Castillo's arrest as a testament to sustained law enforcement persistence and international cooperation. 

FBI Director Kash Patel said the arrest marked the fifth fugitive from the FBI's Ten Most Wanted list captured since early 2025, more than in the previous four years combined. Patel and other officials said the arrest underscores the effectiveness of shared intelligence across borders.

"The work of our agents, federal, state and local partners and the cooperation of Mexican law enforcement brought this fugitive to justice," Patel said in a statement. "We hope this brings some measure of solace to the family of Sandy Ly Le."

Charlotte-Mecklenburg Police Chief Estella D. Patterson said that the case showed the power of collaboration among agencies at every level and sent a clear message that violent offenders cannot escape justice by fleeing U.S. jurisdiction.

At the time of the killing, Castillo was a teenager who had briefly dated Le and owed her money, according to court records and earlier FBI documentation. After a meeting between the two in August 2016, investigators believe Castillo fatally shot her and fled, eventually crossing into Mexico at Nogales, Arizona, shortly thereafter.

Other suspects in the case, including a former girlfriend and another person charged in 2017 with accessory and related offenses, were previously arrested and faced legal action in connection with the case.

The FBI's Ten Most Wanted Fugitives program, established in 1950, has placed more than 530 people on its list, with most apprehended or located through agency efforts and public assistance. Castillo was the 516th person added to that list.

Extradition proceedings are ongoing, and U.S. officials say they expect Castillo to be returned to North Carolina to face first-degree murder and federal unlawful flight to avoid prosecution charges once legal requirements in Mexico are satisfied.