Recent developments have emerged in the Pennsylvania case involving a man accused of murdering his girlfriend, concealing her remains, and setting her vehicle ablaze.

Thomas Stanko, 55, faces charges of criminal homicide linked to the suspected death of 51-year-old Cassandra Gross. Additional charges against him include reckless burning, tampering with evidence, and corpse abuse, according to court documents.

This week, Stanko’s trial commenced in Westmoreland County court. Although Gross’s remains have yet to be discovered, prosecutors argue that Stanko murdered her in the spring of 2018 and meticulously eliminated evidence of his alleged crimes. Stanko has entered a plea of not guilty.

As previously reported by Law&Crime, Gross was last observed in Greensburg on April 7, 2018. The following day, her car was found burned approximately five miles away in Unity Township, while her blind and diabetic dog was located roaming nearby.

Stanko was apprehended a few days after the incident, but formal charges related to Gross’s disappearance were not filed until October 2022. Despite this, he has remained incarcerated since his 2018 arrest, currently serving a federal sentence on unrelated gun charges, as noted by the Pittsburgh Tribune-Review reported.

With no body or murder weapon recovered, prosecutors are building their case on circumstantial evidence, including witness statements, photographs, and text messages. Local reports from ABC affiliate WTAE describe Stanko as a menacing figure.

Voicemails were played in court, with one from October 2017 reportedly containing Stanko asking Gross where she was. “You’re a cheater,” he allegedly said after cursing. “A liar. I’m done.”

Harry Berkey took the stand, saying he lived between Stanko and Stanko’s mother and that in 2018 as he was preparing his house to move in, the defendant came up to him and said “I just want to warn you. I run this area. You’re going to have to play by my rules.”

The neighbor added that he knew Gross’ red Mitsubishi SUV because she would often visit her boyfriend, the TV station reported. She was set to meet him at his home on April 7, 2018, the day she was last seen, authorities contend.

Berkey apparently also recalled that, on April 8, 2018, he saw the red SUV pull up to Stanko’s mother’s residence, though he couldn’t make out who was driving. About 20 minutes later, Stanko’s white pickup truck came by with a backhoe attached to a trailer.

The Mitsubishi then left the defendant’s mother’s house slowly, Berkey said, per WTAE, and the mother and son returned home later that day. Authorities believe Stanko killed Gross and then disposed of her body with the help of his mother, who has since died.

Gross’ mother, Kathe Gross, also took the stand this week, and she said her daughter’s relationship with Stanko began after the missing woman found a note on her apartment door from him stating, “If you want a friend, call this number,” according to local CBS affiliate KDKA.

According to Kathe Gross, her daughter called her multiple times crying and upset, saying Stanko was ringing her doorbell, standing at her kitchen window, or pounding at the home to get in. “If anything happens to me, make sure b knows how much I love him,” Cassandra Gross reportedly wrote to her friend, referencing her son.

The defense has argued that prosecutors have no evidence, with Stanko’s attorney reportedly stating his client had “no motivation” to kill Cassandra Gross.

The trial is expected to last two weeks.