Wisc. Man Convicted of Stalking and Killing His Ex-Girlfriend's Boyfriend Who Went Missing in 2020

Rosalio Gutierrez Jr. was reported missing on May 19, 2020; his girlfriend's ex has now been convicted of his murder

Photo: Proko Funeral Home

A Wisconsin man accused of stalking his ex-girlfriend's boyfriend has been found guilty of his murder.

After 10 hours of deliberating, a jury in a Kenosha County court convicted Zachariah Anderson of intentional murder, hiding a corpse, stalking his ex Sadie Beacham, and her boyfriend Rosalio Gutierrez Jr., according to Law and Crime.

Gutierrez's body still has not been found since he went missing in May 2020, which Anderson's lawyers said during the trial was proof that there was no solid case. However, Kenosha County District Attorney Michael Graveley alleged Anderson was a jealous ex-boyfriend who was mad that Beacham broke up with him.

Anderson had a relationship with his and Beacham's children, but when it came to the exes' romantic relationship, Graveley said she was "ready to move on," per the outlet.

Anderson, who remained stoic and emotionless during the proceedings, will be sentenced on May 16, per Law and Crime.

Anderson's attorney Nicole A. Muller declined to comment to PEOPLE on Wednesday night, citing a pending appeal.

"Having the support of friends, family, people that I don't know – helped give us the strength," Beacham said, according to Fox 6 in Milwaukee.

"I'm eternally grateful. My husband, family and I – Rosalio – finally has justice," added the victim's mother, Selia Patterson.

Beacham called it quits with Anderson in February 2020 before she started communicating with Gutierrez on social media, Fox 6 reported.

During the trial, prosecutors presented DNA evidence and proof that Anderson had been following Gutierrez and going to his apartment before he vanished. He later lied to police about it when they questioned him, per the news station.

Anderson is accused of placing a burner phone in Beacham's car to see where she was going and using a GPS tracker and recording device to stalk her and the victim, according to CourtTV.

Want to keep up with the latest crime coverage? Sign up for PEOPLE's free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases.

The outlet reported that Gutierrez was officially reported missing on May 19, 2020, after police did a welfare check at his apartment. There, they found "large amounts of blood" in his home and Beacham told police that Anderson had been stalking them.

The day Gutierrez went missing, authorities found a burn pit in Anderson's home along with torn clothes and a burned bleach bottle. Anderson's Dodge minivan had Gutierrez's blood in it, along with a piece of carpet that smelled like bleach. Another burn pit was discovered at a tree farm that Anderson's family owns, as well as additional clothes, per CourtTV.

"What are the chances that in this exact square foot on the planet Earth, a man who is innocently and falsely accused, would have the blood of a man who died on May 17? How could that happen?" Graveley challenged during closing arguments, according to Fox 6.