FORT WORTH, Texas (CBSDFW.COM/AP) — A prosecutor says a North Texas man killed and beheaded his roommate and fatally shot the roommate’s 17-year-old girlfriend as she tried to run away two years ago.

Hector Acosta-Ojeda’s capital murder trial for the 2017 killings of Erick Zelaya and Iris Chirinos began Tuesday in Fort Worth.

Hector Acosta-Ojeda

The Fort Worth Star-Telegram reported that Tarrant County Prosecutor Kevin Rousseau said Acosta-Ojeda shot Zelaya twice in the head while he slept.

During the execution of a search warrant, the remains of both Zelaya and Chirinos were found in the backyard of the Burton Drive home.

Zelaya’s severed head was later found on a trail near AT&T Stadium in Arlington, as well as a note written in Spanish about being disloyal.

Human remains found in Arlington (Chopper 11)

Rousseau told the jury that Acosta-Ojeda confessed to the killings, which followed Zelaya saying he shot into an Arlington home Acosta-Ojeda was living in months earlier.

Prosecutors are seeking the death penalty for the 30-year-old.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)