A former Federal Protective Service officer who went on a two-day killing rampage that claimed the life of his estranged wife and two others has pleaded guilty to the school shooting that began the killing spree.

Eulalio Tordil, 63, faces life without parole for the murder of his wife Gladys Tordil and the wounding of a bystander who tried to stop the execution-style attack in the parking lot of High Point High School in Beltsville.

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The May 2016 attack happened as Gladys Tordil was picking up the couple's two daughters from school. The daughters witnessed the murder.

Gladys Tordil was a chemistry teacher at Clarksburg High School in Montgomery County.

Eulaio Tordil later went on a violent spree, shooting and killing two people in the parking lot of Westfield Montgomery Mall and wounding another man. He is due to be sentenced for those crimes in July.

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The murders occurred after Gladys Tordil sought a protective order from her husband. She claimed he had been abusive to both her and her daughters.

Tordil was on leave from his job as a federal security officer. He and had surrendered his service weapon. However, he did not tell authorities about another handgun he owned which was used in the attacks.

He was arrested after the Montgomery Mall shootings at a nearby Boston Market where he had fled after losing his glasses in a botched car-jacking.