A passenger, surveillance video and the accused driver’s statement describe an escalating dispute that ended in gunfire on Milwaukee’s south side.

MILWAUKEE, Wis. — What began as a traffic dispute between two drivers on Milwaukee’s south side stretched across several blocks, moved from insults to pursuit and a minor collision, and ended with 44-year-old Minerva Hernandez-Lopez fatally shot beside her vehicle, according to a criminal complaint and local reporting.

Prosecutors have charged 18-year-old Mariah Ruiz with first-degree reckless homicide while using a dangerous weapon in the Aug. 17 death. The case against Ruiz is built in large part on several forms of evidence that investigators say overlap: neighborhood surveillance footage, audio of gunfire, statements from a 16-year-old passenger riding with Ruiz, evidence recovered after Ruiz surrendered and Ruiz’s own account to detectives. Ruiz is accused but has not been convicted, and later public comments from her mother describe parts of the confrontation differently from the prosecution’s account.

The passenger told investigators that he and Ruiz were driving toward El Rey Supermarket when Ruiz cut off the GMC driven by Hernandez-Lopez. The two vehicles later pulled alongside one another, according to the complaint, and Hernandez-Lopez told Ruiz, “Little girl, you need to drive.” Investigators said Ruiz responded with profanity. The passenger also told police that Ruiz threatened to call immigration authorities after Hernandez-Lopez spoke in Spanish and displayed a handgun during the argument. Hernandez-Lopez then began recording the encounter on her phone, the passenger said, explaining that she believed Ruiz should not have a gun.

The dispute did not end when the drivers initially separated. According to accounts attributed to the passenger and Ruiz, the vehicles continued moving through the neighborhood as one driver followed the other at different points. Hernandez-Lopez eventually got in front of Ruiz’s silver Nissan, and the GMC either stopped abruptly or backed into the front of the Nissan, investigators said. Surveillance footage described in the complaint showed the GMC make contact with Ruiz’s vehicle. That collision became a central point in Ruiz’s later explanation to police, but prosecutors allege her response went far beyond the danger posed by the traffic encounter.

Video and audio evidence described by authorities then recorded the shooting sequence. Investigators said Ruiz was seen extending an arm from her vehicle while holding an object pointed toward Hernandez-Lopez’s GMC. Several shots were heard. More gunfire followed while the GMC was attempting to move away, according to prosecutors and reports citing the complaint. Five spent cartridge casings were recovered, and investigators later linked those casings to a .40-caliber Glock recovered after Ruiz went to a Milwaukee police station with family members. The precise movement of the two vehicles during every shot is an issue likely to remain important as the criminal case proceeds.

Hernandez-Lopez managed to stop near South 10th Street and West Lapham Boulevard and got out of her vehicle after being wounded. A nearby witness, Jesus Ferreira Villarreal, told CBS 58 that he heard a rapid series of gunshots before seeing Hernandez-Lopez seek help. He and other people nearby rushed toward her and attempted to assist until emergency workers arrived. Officers found Hernandez-Lopez outside the driver’s side of the GMC. Despite lifesaving efforts, she was pronounced dead at the scene. The medical examiner ruled her death a homicide after an autopsy documented a fatal gunshot injury.

The passenger’s account supplied investigators with another view from inside Ruiz’s Nissan. He told police that he had tried to stop the situation from escalating and had pulled Ruiz’s hand down at one point because he believed she might fire. He also said he told her not to shoot before the fatal gunfire. Those statements are significant because the passenger was present from the early traffic encounter through the confrontation that prosecutors say became a pursuit. His description also gives authorities a witness account separate from the surveillance cameras and Ruiz’s own later statements.

Ruiz did not remain at the shooting scene. She later went to Milwaukee Police District 2 with family members, including her mother, according to published accounts of the complaint. Ruiz’s mother told officers that her daughter had shot someone and indicated that the firearm was in the vehicle. Police searched the vehicle with consent and recovered the Glock from a bag. A firearms database analysis later found the weapon was consistent with the gun that fired the casings found at the scene, WTMJ reported from the criminal complaint.

During questioning, Ruiz acknowledged firing the gun, according to investigators. She reportedly said she had been having a “bad day” after arguing with her mother before the encounter and told detectives she did not intend to hurt Hernandez-Lopez and did not know why she fired. She also wrote an apology to Hernandez-Lopez’s family, according to reports describing the complaint. Those statements are allegations contained in the prosecution’s case and are not the equivalent of a guilty plea. Prosecutors still must prove the charged offense beyond a reasonable doubt if the case goes to trial.

Ruiz’s mother has since offered public comments that put greater emphasis on her daughter’s fear during the encounter. She told WTMJ that Ruiz called her while the incident was unfolding, sounded frightened and said Hernandez-Lopez was following her and preventing her from leaving. Ruiz also told investigators that Hernandez-Lopez blocked her and backed the GMC into the Nissan before she opened fire. Those claims do not erase the portions of the complaint describing Ruiz as pursuing Hernandez-Lopez at other points, and prosecutors allege Ruiz continued firing as the other vehicle tried to get away. The competing descriptions leave questions about the drivers’ movements and perceptions for the court process to examine.

The charge against Ruiz is first-degree reckless homicide with a dangerous-weapon enhancer. Wisconsin prosecutors allege that her actions created an unreasonable and substantial risk of death while showing utter disregard for human life, the elements associated with the offense they selected rather than an intentional-homicide count. Local reports said the homicide charge can carry up to 60 years in prison, with up to five additional years connected to the weapon allegation if Ruiz is convicted and the enhancer applies. Her cash bond was set at $100,000.

The case also illustrates why the sequence captured by cameras, witnesses and physical evidence matters more than any single phrase exchanged between the motorists. The comment Hernandez-Lopez allegedly made about Ruiz’s driving has drawn attention because it occurred near the beginning of the conflict, but investigators describe a longer chain of conduct afterward: threats, a displayed gun, recording by cellphone, vehicles following one another, a collision and multiple shots. Prosecutors will have to establish how those events fit the charged crime, while Ruiz has the right to challenge the state’s evidence and present a defense.

Hernandez-Lopez’s relatives returned to the area after the killing and remembered her as a mother, wife and sister, according to local television coverage. Published reports have differed on the number of children she had, so that detail remains omitted here rather than treated as settled. What is not disputed in the available reporting is that Hernandez-Lopez died at the scene after bystanders tried to save her, and that her death left family members grieving while a homicide prosecution began.

Ruiz made an initial court appearance in August, when a judge found sufficient cause to hold her for further proceedings and imposed the $100,000 cash bond. A Sept. 3 local report said another hearing was scheduled for Sept. 17. Searches of publicly available reporting through Sept. 29 did not establish the outcome of that hearing or a newer confirmed trial date. Ruiz therefore remains accused of the offense, and the allegations against her have not been proven at trial.

Author note: Last updated September 29, 2026.