SAN ANTONIO, Texas (AP) - Authorities accuse a man of fatally shooting his ex-wife and her older brother after an argument when he went to a relative's house in Bexar County to get their 7-year-old son.

Bexar County sheriff's Sgt. Raymond Pollard said the shooting occurred Wednesday night when the man, whose name was not released, went to the house to pick up his son for a visit.

Witnesses told the San Antonio Express News that the 48-year-old mother argued with the man outside the house before running inside yelling, "He's got a gun!"

Pollard says the man followed, shot her several times and gunned down her 57-year-old brother when he tried to help.

The man, who was in his 40s, then fled.

The victim's names were not immediately released.

The boy was unharmed.