02:18 - Source: CNN
Teen gunman 'roamed' through neighborhood prior to shooting spree, says New Mexico police chief
CNN  — 

The 18-year-old gunman who killed three elderly women out on morning drives in a northwestern New Mexico neighborhood this week fired more than 100 rounds from his yard before leaving the property with two pistols and wearing a bulletproof vest, Farmington Police Chief Steve Hebbe said at a news conference Wednesday.

Gwendolyn Schofield, 98, her daughter Melody Ivie, 73, and Shirley Voita, 79, were slain Monday by Beau Adam Wilson, who was shot dead by responding police officers.

Six others, including two police officers, were wounded in what’s become one of 226 mass shootings – with four or more victims shot – this year in the US, with people often falling prey while out for everyday tasks like grocery shopping, attending school and going to work.

Seven other people suffered injuries that were treated at the scene.

Voita Family/Farmington Police Department
Shirley Voita, 79, was one of the three women killed.

Investigators continue to work to pin down the motive for yet another deadly episode in America’s gun violence plague. Hebbe said authorities found a short, handwritten note in the gunman’s pocket, and are trying to “piece together” the note’s meaning as part of the investigation into his motive.

Some relatives interviewed by law enforcement expressed concerns about Wilson’s mental health, Deputy Chief Kyle Dowdy said at Tuesday’s media briefing, adding it’s not clear whether he had been diagnosed with any issues. Wilson had only “minor infractions” with law enforcement before the violent attack, the deputy chief said.

Hebbe told reporters Wednesday mental health issues appear to be a factor in the shootings.

“We’ll end up finding in the next couple of days what medication if any he was under, if he was under a doctor’s care in some form or fashion,” Hebbe said.

The shootings started Monday morning as the gunman stood outside his house, firing at vehicles with an AR-15-style rifle, the chief said. According to San Juan County sheriff’s Capt. Kevin Burns, the gunman fired at least 141 .223 caliber bullets from his property.

Hebbe said the gunman dropped the semiautomatic rifle in the bushes by his house and the rifle still had a round in the firing chamber and ammunition in the magazine.

Susan Montoya Bryan/AP
Community members sing during a prayer vigil Monday in Farmington, New Mexico.

The gunman left the property with two pistols – a .22 and 9 mm – to shoot as he walked toward a church, where he was killed, the chief said. There were 10 other guns left behind in the house, according to Hebbe.

“The last two (guns) the suspect took with him as he began walking and he was firing around the neighborhood, and firing at other cars and houses,” the chief said.

Doorbell camera video shows the shooter was wearing a bulletproof vest, similar to what police officers wear, but by the time the gunman “made his last stand” at the church, he had removed his vest, according to Hebbe.

The 9 mm pistol was empty of ammunition when found on the deceased gunman, Hebbe said.

More than 200 911 calls flooded in to authorities as gunfire reverberated through the neighborhood, nestled in a commercial hub near the Southwest’s Four Corners.

Authorities have said they believe two of the guns used in the rampage were owned by a family member of Wilson, who turned 18 in October and purchased the third gun in November. The shooter purchased three magazines for rifle just two days before the rampage, the chief said.

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“We’re certainly looking at the circumstances by which he procured the AR-15 and some of the other weapons, and part of the investigation will take us into what were the circumstances by which the other weapons had been obtained,” the chief said when asked whether family members could face charges, “but no, at this point in time, we’re not holding anybody responsible.”

Besides the 10 guns left inside the house, there were also 1,400 rounds of ammunition available to the shooter, according to the chief.

CNN’s Amy Simonson contributed to this report.