Case:          25-2230838
 
Date:          Monday, August 11, 2025
 
Time:         2:15 p.m.
 
Location:   8601 Research Boulevard Northbound (Target parking lot)
 
Deceased adult victim: Hector Leopoldo Martinez Machuca, Hispanic male, 4-7-2001
 
Deceased victim: Adam Chow, Asian male, 8-18-1959
 
Deceased Juvenile victim: 4-year-old
 
Arrested: Ethan Nieneker, White male, 32 years of age

On Monday, August 11, 2025, at approximately 2:15 p.m., Austin Police Department (APD) officers responded to calls of multiple shootings at the Target parking lot at 8601 Research Boulevard northbound. Officers arrived to find a male, later identified as Hector Leopoldo Martinez Machuca, in the parking lot. Mr. Martinez Machuca was transported to the hospital where he was later pronounced deceased at 3:01 p.m. Officers also located a family including Adam Chow, his wife, and their 4-year-old granddaughter. Adam Chow and his 4-year-old granddaughter were pronounced deceased on scene. Mr. Chow’s wife sustained minor injuries.
 
Homicides Detectives and Crime Scene Specialists responded to process the scene and interview witnesses. The investigation showed Ethan Nieneker randomly attacked a Target employee Hector Leopoldo Martinez Machuca in the parking lot, shooting and killing him as he was collecting shopping carts. Nieneker then ran to a black Jeep Cherokee and began firing as the Jeep attempted to evade the gunfire. Nieneker then ran up to a gray Toyota 4-Runner where he shot Mr. Chow as he sat in the driver seat. He then fired into the backseat, striking the 4-year-old granddaughter. Mr. Chow’s wife carried their granddaughter from the vehicle and Nieneker pushed her from the vehicle. Nieneker then drove the Toyota from the parking lot at a high rate of speed. Mr. Chow and the 4-year-old granddaughter were pronounced deceased on scene at 2:39 and 2:50 p.m.
 
At approximately 2:20 p.m. Nieneker found a water truck parked alongside the 7800 block of Mopac Expressway. He opened the driver’s door and repeatedly assaulted the driver before pushing him out of the vehicle. He attempted to put the truck into drive but was unable to. He then jumped out of the truck and chased a male with a pistol in his hand before running back to the stolen 4-Runner and drove off.
 
At approximately 2:25 p.m., APD received the call of a multiple-vehicle crash as the stolen 4-Runner crashed into a Volkswagen before landing on top of an Infiniti SUV. Nieneker exited the vehicle and went over to the Volkswagen, opened the door and repeatedly assaulted the female driver of the Volkswagen. He pushed the female driver of the Volkswagen out  and then drove off.
 
At 2:34 p.m., a suspect matching Nieneker’s description exited the stolen Volkswagen and went up to a Waymo vehicle and attempted to break into it. This failed and Nieneker returned to the stolen Volkswagen and drove away.
 
At 2:37 p.m., an acquaintance known to Nieneker through bible study reported that Nieneker had thrown a brick through his residence in the 2100 block of La Casa Drive. 
 
At 2:58 p.m., APD received the call of a naked male walking through a backyard in the 2400 block of La Casa Drive. Nieneker was observed running into a “porta potty” and then leaving on foot. Officers located Nieneker walking naked on Montclaire Street. Nieneker was issued commands, did not comply, was tased and taken into custody at 3:06 p.m. Officers checked the area, and the matching suspect clothing previously captured surveillance was located inside of the "porta potty".
 
The investigation shows that Nieneker conducted these violent offenses of shooting at multiple victims, killing three victims, and destroying multiple vehicles, in the span of less than one hour.
 
Nieneker has been charged with two counts of Capital Murder for the 4-year-old granddaughter and for Adam Chow. He has also been charged for the First-Degree Felony Murder of Mr. Martinez Machuca.
 
Detectives are encouraging anyone who may have photos, videos, or potential evidence, please submit them by clicking here or scanning the QR code below.
 

Anyone with information is asked to contact the Austin Police Department at 512-974-TIPS. You may submit your tip anonymously through the Capital Area Crime Stoppers Program by visiting austincrimestoppers.org or calling (512) 472-8477. A reward of up to $1,000 may be available for any information that leads to an arrest.
 
This case is being investigated as Austin's 39th, 40th and 41st homicide of 2025.