Mayra Velasquez, 42, was arrested Monday, July 20, and charged with capital murder in the death of 32-year-old Irasema Chavez-Sanchez.

ARLINGTON, Texas — Newly released court documents reveal that DNA evidence was the key breakthrough that led Arlington police to arrest a woman in the 2012 killing of her close friend, a case that had remained unsolved for more than 14 years.

Mayra Velasquez, 42, was arrested Monday, July 20, and charged with capital murder in the death of 32-year-old Irasema Chavez-Sanchez. 



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Police allege Chavez-Sanchez was killed while Velasquez was committing or attempting to commit a robbery on Jan. 19, 2012. 

Chavez-Sanchez was found dead the next day inside her apartment in the 2700 block of South Collins Street after a family member discovered her covered in blood. The Tarrant County Medical Examiner’s Office ruled her death a homicide, determining she had been stabbed more than 100 times.

Arlington police and the FBI Dallas Field Office are scheduled to provide more details during a joint news conference on Wednesday, July 22.


DNA evidence remained unsolved for years

Investigators said Chavez-Sanchez had installed surveillance cameras in 2011 after someone slashed a tire on her vehicle. Detectives recovered the apartment’s digital video recorder and determined the final footage showed Chavez-Sanchez arriving home in the evening on Jan. 19, 2012.

About four hours later, surveillance video captured a person wearing baggy sweatpants and a hooded sweatshirt knocking on her apartment door before Chavez-Sanchez voluntarily let the person inside. Less than 10 minutes later, power to the surveillance system was disconnected, ending the recording, according to the affidavit.

Crime scene investigators documented bloody shoeprints throughout the apartment leading toward the victim’s bedroom television, the missing living room television and the front door. 

While processing the scene, investigators also found a quarter-sized blood droplet on the lower shelf of the bedroom television stand. According to the affidavit, the blood appeared fresh and was drying at the same rate as blood found near Chavez-Sanchez’s body.

Testing determined the blood belonged to an unknown Hispanic female and did not match Chavez-Sanchez. Investigators entered the DNA profile into the Combined DNA Index System, or CODIS, but no match was found.

Police also released surveillance images to the public and pursued numerous leads between 2012 and 2024, but investigators were unable to identify a suspect.


Forensic genealogy provides breakthrough

The investigation changed after additional DNA testing was conducted in December 2024.

According to the affidavit, the testing identified a relative of the unknown female DNA contributor. Detectives used family lineage research to identify Velasquez as a potential suspect. 

On May 13, undercover detectives conducting surveillance watched Velasquez eat at a restaurant with friends. Investigators collected two plastic forks, a plate and a cup they said she left on the table when she exited the restaurant. 

A state crime laboratory later determined DNA recovered from one of the forks matched the DNA profile developed from the blood droplet found inside Chavez-Sanchez’s apartment the night she was murdered. 


Investigators say women were close friends

The affidavit states detectives learned Velasquez and Chavez-Sanchez were close friends and lived less than four miles apart at the time of the killing from Chavez-Sanchez’s cellphone records. 

According to the affidavit, detectives received a tip shortly after the homicide that Velasquez’s husband was jealous of the women’s relationship. Detectives went to the couple’s home and left a business card requesting they contact investigators after a relative confirmed the couple lived there, but neither Velasquez nor her husband called police.

Authorities have not publicly identified a motive beyond the capital murder allegation that the killing occurred during the commission or attempted commission of a robbery.

Velasquez had no prior criminal history, according to the affidavit.

She was arrested Monday with assistance from the FBI and the Dallas Police Department. Arlington police said the investigation remains ongoing, and anyone with information about the case is encouraged to contact the Arlington Police Department.