Investigators say witness statements, ammunition and a video from inside the house tied the 21-year-old suspect to the killing of Sheri Tolosa, 44.
SAN ANTONIO, TX — San Antonio police have arrested a 21-year-old man in the killing of a 44-year-old woman who was found shot to death inside a Northwest Side home this week, turning a welfare check on Donaldson Avenue into a homicide case that now centers on witness accounts, shell casings and statements investigators say only the shooter would have known.
Sheri Tolosa was found dead Monday inside the home near Donaldson Avenue and Manor Drive after officers were called there for a welfare check. By Thursday, investigators had filed a murder charge against Aaron Arocha, who police say had been inside the residence earlier in the day with permission and was later linked to the case through relatives’ statements, vehicle data and ammunition recovered after his detention. The arrest marked a major step in a case that had, at first, few public answers beyond the discovery of a woman killed inside a locked home.
The investigation began just after 12:30 p.m. Monday, when police were called to the 1000 block of Donaldson Avenue after the homeowner, who was away from the property, reported hearing from a relative that there had been a shooting inside the house. Officers initially responded to the address as part of a welfare check. According to police accounts, the house appeared secure from the outside and showed no immediate sign of forced entry. Later that afternoon, officers entered the residence and found Tolosa dead with multiple gunshot wounds. On Wednesday, the Bexar County Medical Examiner’s Office publicly identified her and ruled her death a homicide. Early reporting from the scene described gunshot wounds to her upper body. Later court records described a more detailed picture, with investigators saying she had been shot in the head and face and that shell casings were found in more than one room.
Police said the case began to narrow Tuesday morning, when officers located a man they wanted to question at a business on South General McMullen Drive near Monterey Street. Investigators had developed information about a vehicle possibly connected to the homicide, and an officer found a car matching that description and license plate. When police tried to contact the man, he fought with officers, according to an investigator quoted at the scene, and was taken into custody after what authorities described as a physical altercation. At that point, police said they were still trying to determine whether he would be treated as a suspect, a witness or someone who might simply know something about the shooting. By Thursday, however, investigators said the man was Arocha and that evidence gathered since the detention had pushed the case toward a murder charge.
According to the arrest report described in local coverage, Arocha had been at the house earlier Monday to work on a refrigerator and had permission to be there. Investigators said messages between him and the homeowner supported that point, and they noted there was no sign anyone had broken into the residence. Inside the home, detectives said they found Tolosa in the kitchen near the back door. They said the location of the body and the spread of shell casings suggested the shooting may have started in the dining room and continued as Tolosa moved toward an exit. Officers recovered five shell casings, and investigators later said Arocha’s vehicle contained a box of .380-caliber ammunition in the center console. They said the caliber and brand matched casings recovered at the house and that several rounds were missing from the box.
Investigators also said digital and witness evidence helped build the case. One report said Arocha sent a video from inside the home in which he showed a bruise on his knee and said Tolosa had caused it. Police said that detail stood out because it placed him inside the residence close to the time of the killing. Detectives also used license plate reader data to trace the vehicle they say he was driving. According to investigators, that data placed the vehicle in the Houston area Tuesday before it appeared to head back toward San Antonio later the same day. Police eventually detained him in San Antonio while he was driving that vehicle, first on charges including interference with public duties and resisting arrest, then later in connection with Tolosa’s death.
Statements from relatives appear to have played a central role in moving the case from a broad homicide investigation to a formal murder filing. Investigators said one family member told them Arocha called the night after the killing and first claimed he had found a dead body. Other relatives, police said, told them Arocha had admitted he shot someone. In one of the most striking allegations in the report, a relative told investigators Arocha later met with him and confessed to the shooting, saying “Santa Muerte told him to do it.” That same witness said Arocha claimed Tolosa had done nothing to provoke the attack and that he planned to leave Texas for Houston and Arizona afterward. Investigators said some of the details relayed by relatives matched facts that had not been publicly released at the time, including the number of shots and the nature of Tolosa’s injuries, which they argued suggested inside knowledge of the crime.
The case also reflects how little was clear in the first hours after Tolosa’s body was found. Officers initially said they did not know exactly how the first information about the shooting reached the homeowner or who first reported that someone had been shot inside the residence. They also said they were trying to understand the relationships among the people involved and the circumstances that led to the shooting. Even after Arocha was detained Tuesday, police publicly stressed that his exact role was still uncertain. That changed only after detectives reviewed physical evidence, statements and vehicle data over the next two days. The progression from an uncertain welfare check to a named murder charge shows how homicide cases can develop in stages, with investigators first securing the scene, then matching witness statements against forensic details and movement records.
Several questions still have not been answered publicly. Investigators have not described a clear motive beyond the statements attributed to Arocha by relatives. Police also have not publicly explained the nature of Tolosa’s relationship with Arocha, beyond saying he had permission to be inside the home and had been doing work there earlier in the day. It is also not clear whether prosecutors will pursue any additional charges tied to his initial detention and resistance during the Tuesday encounter with officers. No court filing released publicly so far has laid out a fuller narrative of what happened inside the house in the minutes before the gunfire. Authorities also have not publicly announced a bond amount in the murder case or provided a date for a first major court hearing on the charge.
For neighbors, the case began with police tape, patrol cars and a confusing scene at a home that from the outside showed little sign of the violence inside. The address sits in a residential stretch on the Northwest Side where the first public sign of trouble came not from a 911 call made inside the home, but from relatives and the homeowner trying to make contact from elsewhere. Officers arriving for what began as a welfare check soon shifted to a homicide investigation. In the days that followed, the case drew steady local attention as investigators searched for who had been in the home, tracked a vehicle across Texas and pieced together conflicting early accounts from relatives. By Friday morning, the story had moved from unanswered questions about a woman found dead in her kitchen to a murder case against a young San Antonio man.
As of Friday, Arocha had been charged with murder in Tolosa’s death, and police said the investigation remained ongoing. The next public milestone is expected to come in court, where magistrate and filing records should begin to show bond, hearing dates and any additional allegations as prosecutors move the case forward.
Author note: Last updated April 17, 2026.