Updated

Police have charged a 16-year-old girl and her boyfriend with capital murder in the fatal shooting of a grandfather who was protecting his family from masked intruders in his Dallas home.

Dallas police Lt. David Pughes said the girl and 17-year-old Jose Alfaro were arrested after a brief standoff at a Dallas home Monday night. Police aren't identifying the girl, who has been charged as a juvenile. Alfaro faces adult charges.

Pughes says police don't know the motive. He said the girl and a granddaughter of the victim, 66-year-old Lorenzo Moreno, were friends who had fallen out. Police are seeking four other suspects in the Sunday shooting.

Alfaro is being held in the Dallas County jail on $1 million bond. There is no attorney listed in online jail records.