Tustin police arrested 47-year-old Juan Marquez in connection with the fatal shooting of his ex-girlfriend, 42-year-old Sandra Fernandez.The incident occurred on Thursday near the intersection of Yorba Street and Medford Avenue, where Fernandez, an Anaheim resident and single mother of three, was found unresponsive with gunshot wounds and pronounced dead at the scene.

Authorities reported that Marquez, a resident of Hawthorne, waited near Fernandez’s workplace and fled the country through the San Ysidro Port of Entry after the homicide.Following an arrest warrant, U.S.Customs and Border Protection detained Marquez as he attempted to return to the United States.He was then taken into custody by Tustin detectives and booked into Orange County Jail on a murder charge, held without bail.Fernandez had recently started a new job and was returning home from training at the time of the shooting.The case highlights issues of domestic violence and cross-border law enforcement coordination.