The recent footage was filmed several hundred yards from the Island Bay Resort apartment pool.
"It looks like an adult man hit a child," Lozano, who witnessed the melee, can be heard saying during a 911 call while the encounter plays out in the distance.
Lazano said she and her boys were swimming at the nearby dock when they placed that 911 call.
When a uniformed officer arrived, her boys, 15 and 23 years old, went to help, fearing the man they saw hitting children would turn on the cop. By the time they got to the pool, they said more officers showed up, so they backed off.
Lozano claims that's when the man, indentified as Offucer Rivas, came after them.
"He ran up to us screaming, 'Stop, where are you going? Come back.' So my 15-year-old son turned around and said 'Yes sir,' and at that point, he reached up, grabbed him by the neck, and slammed him to the ground," Lozano said.
Lozano said she told Rivas to stop.
She tells ABC13 that Rivas stood up and got in her face. When her 23-year-old son tries to explain that they weren't at the pool, Rivas is then accused of throwing the 23-year-old to the ground and getting on top of him. Lozano pulled out her phone and captured a video of her adult son getting hit in the head multiple times by Rivas.
"Are you (expletive) kidding me? What are you punching my son for?" Lozano can be heard yelling in the video.
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Lozano said both her sons were cuffed and put in cars before being released. She took them both to the hospital to be checked out shortly after.
Lozano's older son expects to press charges against Rivas, who they want to be removed from the force.
"He is a bad apple, a loose cannon, and very dangerous. I feel like if he had his duty weapon on him at that time, our children would have been seriously injured; I think someone would have lost their lives," Lozano said.
ABC13 contacted Rivas for his recollection of the story, but he hung up.
"Body camera footage gave cause for alarm regarding the conduct of Officer Rivas," Galveston Police Chief Doug Balli said.
Galveston police and the police union of which Rivas is a member have yet to make themselves available to speak with Eyewitness News.
Police said Rivas was at the pool as an off-duty security guard; however, the apartment complex told ABC13 that Rivas was not an employee.
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