It has been reported that San Antonio police sought a motive on Thursday night in an alleged triple-murder-suicide by a 69-year-old man in an upscale gated community.

Sgt. Chris Benavides has said that the alleged shooter was Joseph Ray McDonald, the stepson of homeowner Arthur DeBaun, 88, found dead alongside Heather Monroe, 40, and Jeffery Monroe, 41.

Benavides said that Jeffrey Monroe was Heather Monroe's estranged husband.

The San Antonio Express-News quoted Benavides as saying, "We still don't have a clear motive."

According to Benavides, Heather Monroe and her three children were moving in with DeBaun.

Benavides further said that the shooting in San Antonio's wealthy north side occurred as the children, identified only as two boys, ages 14 and 10, and an 8-year-old girl, played outside nearby, possibly coaxed outside by McDonald before he opened fire with two handguns he'd packed in a briefcase.

As the shooting began, the 14-year-old boy immediately hustled his brother and sister out of the yard and down the street to a neighbor's house, where he could see a party was going on. They called police.

The Express-News quoted Benavides as saying, "(The boy) showed a lot of courage in getting his two younger siblings to safety at his neighbor's home."

Police records have indicated that McDonald had no criminal history. (With Inputs from Agencies)