Inset: Dillon Michael Hill (Dallas County Jail). Background: The area near where Hill allegedly fatally beat a man in Dallas, Texas (Google Maps).

A Texas man is behind bars for ultimately causing the death of another man after a late-night beating outside a business in Dallas, according to law enforcement in the Lone Star State.

Earlier this month, Dillon Michael Hill, 34, was charged with one count of aggravated assault causing serious bodily injury in the second degree over an incident that injured 50-year-old John David Zuniga.

The underlying incident occurred during the early morning hours on July 5 at a location along Harry Hines Boulevard near the Market Center station of the Dallas Area Rapid Transit rail system.

On July 9, Zuniga succumbed to his injuries and died at Parkland Hospital, according to the Dallas Police Department.

Now, Hill is charged with one count of murder, jail records show.

On the night in question, a security guard heard loud banging around 1:50 a.m. and went outside to find Hill, who he described as tall and muscular, standing over Zuniga on an elevated patio entrance and repeatedly striking the victim with closed fists, according to an arrest affidavit obtained by Dallas-based Fox affiliate KDFW.

Bystanders eventually separated Hill from Zuniga, police said. During the extrication process, the assailant allegedly shouted taunts at the victim such as "You don't know me," and "I'm a killer."

Then, after the two men were separated, the defendant struck Zuniga once again — this time by rearing back and punching him in the face with his closed right fist, according to the affidavit. The final blow caused the victim to fall backward down the nearby patio stairs and strike his head on the pavement, witnesses told law enforcement.

By the time first responders arrived, the victim was unresponsive and without a pulse, police said. He was then rushed to the hospital, where he was diagnosed with a fractured skull and brain bleed that required intubation to breathe, the charging document says.

Hill allegedly left the scene in a white Chevrolet Malibu, but law enforcement tracked the vehicle to a separate disturbance the defendant had caused on Maple Avenue and arrested him, police said.

During a custodial interview, Hill told investigators that he and Zuniga were arguing when the victim raised his shirt to show off a knife. The defendant said the sight of the knife threatened him, so he punched the other man in the face, according to the affidavit. Police, however, said the victim did not have a knife on him during CPR efforts at the crime scene and that no such weapon was found at the scene either.

The investigation is said to be ongoing. Hill is currently detained in the Dallas County Jail on $1.5 million bond.