A 4-year-old girl − one of five relatives shot after unidentified gunmen unloaded at least 30 rounds into their San Antonio home − has died, officials said Thursday.

The shooting, captured on neighbor's surveillance cameras, took place about a half-hour before sunset Wednesday night at a San Antonio townhome where the girl lived with her siblings, age 7 and 8, and and the children's parents, Bexar County Sheriff Javier Salazar reported.

First responders transported all five victims the San Antonio Military Medical Center in critical condition, according to Salazar.

The 4-year-old girl, whose name has not yet been released, died at the hospital, the sheriff said during a Thursday night news conference in which he released footage of the shooting to the media.

As of Friday, the other victims remained hospitalized, a sheriff's spokesperson said, and their conditions were not immediatly known.

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Who are the gunman who opened fire on the San Antonio home?

As of Friday, the gunman had not been identified publicly by law enforcement and no arrests had been made in the shooting.

But during Thursday's press conference, the sheriff said there are persons of interest being investigated in connection to the case.

"We're pretty certain we're hot on their tracks," he said, adding he could not elaborate about the suspects.

The gunman and the victims apparently knew each other, the sheriff said.

"I have no doubt that they were after the people in that home for whatever reason," Salazar said. "These were people who were absolutely there to take lives last night... They wanted to empty enough lead into that home to make sure that they inflicted maximum damage. To make sure that they killed somebody."

"Is it going to give me great pleasure to charge both of these two guys with capital murder when the time comes? Absolutely," the sheriff said. "It's just something we can't allow to happen anywhere, to anyone much less a 4-year-old child who had nothing to do with anything."

30 rounds recovered from scene, police say

Disturbing footage released by the sheriff's office, shows two suspects wearing ski masks pull up to the townhome in a vehicle believed to be an Infiniti sedan, Salazar said.

The vehicle parks beside a white box truck and the suspects are seen getting out of the vehicle, running up to the home where they unleash a barrage of bullets from semi-automatic rifles into the house.

The men then get back into the vehicle with the high-powered weapons and flee the scene.

Investigators, the sheriff reported, found a least 30 shell casings at the scene.

Anyone with informatoin about the shooting is asked to contact the sheriff's office.

Natalie Neysa Alund is a senior correspondent for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.