SAN ANTONIO (AP) - A domestic dispute at a South Texas home has left a man shot to death and police searching for his ex-girlfriend's son who allegedly opened fire.

San Antonio police say the 23-year-old son fled early Thursday after gunfire during the argument between his mother and her former boyfriend.

Police say the 44-year-old ex-boyfriend showed up at the woman's home and allegedly started to beat her while accusing her of seeing other men. Police say the son tried to intervene and ended up shooting the older man. Authorities say the suspect, who's expected to face a murder charge, fled with his own toddler son.

The name of the man who was killed wasn't immediately released.

Further details weren't immediately available.

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