A man was fatally shot in the head outside a south San Antonio apartment early Monday morning.

San Antonio police responded to a call for shots fired around 2:45 a.m. at the Montrose Place Apartments in the 400 block of Montrose.

Officers arrived and found a man lying on a second-floor landing with a gunshot wound to the head. He was pronounced dead at the scene.

"I heard two gunshots, and then I just went and checked on my kids, and I just left it alone, because I don't want any violence toward my house," said a neighbor.

SAPD investigators believe the victim answered a knock at the front door from a man looking for his girlfriend.

Witnesses told police the man had come to the apartment looking for his girlfriend before, and the victim said he would handle it.

The two men got into an argument on a second-floor balcony, then the visitor -- identified by police late Monday afternoon as 36-year-old Valdemar Valdez -- pulled out a gun and fired two to three shots, hitting the other man in the head, San Antonio police said.

"It's crazy. I mean, the neighborhood is quiet, but you know, I just mind my business, go to work and come home. But then you hear about stuff like that, and it was right here. I was in my living room," said Nathaniel Williams, who lives in an apartment underneath the scene of the shooting.

A short time after the shooting was reported, officers detained a man later determined to be Valdez not far from the apartment complex, police said.

Investigators also believe they found the weapon used in the shooting, which was dumped in the same area at Caldwell and Presa.

Valdez is being held on a $100,000 bond on a charge of murder.

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