An arrest warrant was put out for Henry Solis back in March after Salome Rodriguez was killed after getting into a bar fight in California.
After being on the run for several months he was caught in Northern Mexico from which he was flown to the US and held in El Paso.
Solis' father, Victor, was arrested in late March for allegedly lying to the FBI after helping his son flee to Mexico
Speaking about the development, Rodriguez's mother Lidia said: "I felt blessed, like God is hearing us.
"The only thing we kept on doing is praying and asking people on Facebook, friends and family, to keep on praying."
The FBI are expected to give a further update on Wednesday. Police had put a reward of up to $25,000 for information leading directly to the arrest of Henry Solis.