The Galveston County District Attorney has identified the suspect as Athir Murady.
According to District Attorney Jack Roady, Murady is charged with the felony offense of evading arrest.
"He is being treated in the hospital. Our office will request that he be denied bail," Roady disclosed in a statement Wednesday.
The Galveston Police Department said it received information about a "be on the lookout" alert for a vehicle and license plate belonging to the suspect vehicle involved in Cpl. Maher Husseini's murder, which authorities said occurred a couple of hours earlier and 60 miles away in southwest Houston.
According to Galveston PD, Sgt. Nick Yeley, a deputy city marshal responsible for code enforcement, noticed the vehicle that matched the description in a parking lot in the 6700 block of Broadway while driving home from work. He was on the phone with his father.
"By chance, by fate," he explained, "I looked over and I told my dad, 'I gotta go.'"
A car matching the description he had heard over the city's dispatch system had backed into the Sleep Inn and Suites parking lot on Broadway.
Sgt. Yeley said he considered approaching it alone, but he was in his personal car and didn't have a bulletproof vest. He thought about his own seven children and what would be his most effective strategy.
"Everything slowed down. I was able to visually see every descriptor in that vehicle," he said. "I was able to see the suspect, and the feeling that I had was, 'Am I going to be quick enough to make the phone call to get the calvary there?'"
He said officers arrived in less than a minute.
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As they staged nearby, he watched the suspect take off. Police chased him down Broadway, through the Channelview neighborhood, until he drove right into the bay. He treaded water for nearly half an hour.
When a law enforcement boat finally got him out, police say he kept resisting, even after a police K-9 bit him.
"I kind of watch it, and I kind of don't want to watch it because I know what happened earlier in the day," Sgt. Yeley said. "We're all family; we all wear a uniform. We're all sisters and brothers in this, and when one of my brothers goes down, it hurts my heart, and I want to say his family is in our prayers. It's hard for us."
While a murder charge remains pending, authorities accuse Murady of shooting and killing Husseini while he was inside his vehicle at a red light on Tuesday.
ABC13 spoke with a man who says he knew Murady through a family friend.
Sebastian Dimas said he hadn't seen the now-suspect in about two years but never saw signs that Murady was capable of such allegations.
"I was shocked," Dimas said.
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The suspect allegedly got out of his own vehicle on Richmond Avenue at Fondren Road, went up to Husseini, and shot him.
Husseini was taken to Ben Taub Hospital, where he was pronounced dead.
Surveillance video obtained by ABC13 shows the suspect running away after the gunfire.
Officials initially identified their suspect as an Asian/Middle Eastern man between 35 and 40 years old.
The suspect took off after the shooting but was later spotted in the League City area before driving his vehicle into the water.
So far, it's unclear if the suspect and Husseini knew each other. Houston Police Chief Noe Diaz said that is part of the investigation.
"I don't have the information to give you now about what occurred, but our homicide division is working around the clock to get that information," Diaz said. "We still have to get a lot of interviews. There is video near the area from businesses, so we will work all that together to make sure we provide the facts to the community."
Dimas said he wouldn't know whether Murady had a relationship with Husseini before Tuesday's shooting.
Additional charges are likely pending for Murady as the investigation continues.
"Hopefully, if he's found guilty, he gets what he deserves," said Dimas. "I pray for (Husseini's) family, as well."
Pct. 4 Constable Mark Herman said he promoted Husseini, who has been with the agency since 2021, a week ago.
Husseini's brother told ABC13 he was married and leaves behind children.
On Tuesday night, a somber procession carried Husseini's body in a flag-draped casket from Ben Taub Hospital in the Medical Center to the Medical Examiner's Office.
"It's too much. There's total chaos in our communities and we got to get it fixed," Herman said outside of the hospital. "My mentality with law enforcement, and all of you know me, is to fight, fight, fight. The only thing these criminals understand is force."
Texas Gov. Greg Abbott weighed in on the brutal murder, saying, "The dangerous criminal who ambushed and murdered Deputy Constable Husseini will have the full weight of the law brought down upon him."
On Wednesday evening, Constable Herman's office released details of Husseini's funeral at Masjid Alsalem Mosque at 16700 Old Louetta Road in Spring. The funeral on Thursday begins at 1:45 p.m.
A condolence gathering will occur at the Arab American Cultural and Community Center at 10555 Stancliff Road in Houston from 6 p.m. to 9 p.m. Thursday.