Texas police
A police officer stands next to an unattended vehicle at Terminal B baggage claim level after a gunman opened fire at the terminal in George Bush Intercontinental Airport in Houston, Texas, May 2, 2013. Reuters/F. Carter Smith

An 18-year veteran of the Little Elm Police Department, Texas, Jerry Walker, was fatally shot and killed Tuesday afternoon during a standoff with a gunman that stretched for hours and forced dozens of neighbors to evacuate.

Detective Walker died at a hospital, said Little Elm Police Chief Rodney Harrison at a news conference Tuesday night. Walker, 48, was among the first Little Elm officers who responded to the call from 1400 block of Turtle Cove around 3 p.m. (4 p.m. EST) after someone reported seeing a man with a "long gun." Denton County sheriff's Lt. Orlando Hinojosa reportedly said that officers heard a man screaming at them from the backyard of the home, and they backed away when they saw a gun. Between 3 p.m. and 4 p.m., the man went into the home and started shooting through a window or a door, and officers fired back.

Walker was shot in the upper body, and other officers were able to get him to a vehicle and take him away from the scene. He was taken by air ambulance to Medical City Denton, where he later died.

The shooter remained barricaded in a home in the 1400 block of Turtle Cove Drive. Police had evacuated residents from nearby homes. The Denton County Sheriff’s Office confirmed that the standoff in Little Elm is over and the man who allegedly shot and killed Walker is dead.

Walker, who was promoted to detective in 2013, has four children, the youngest a few months old and the oldest 22. "He was a model officer and someone who will be missed by the department and here in the town of Little Elm," Harrison reportedly said. Walker is the first North Texas officer to be fatally shot in the line of duty since the ambush on officers in downtown Dallas on July 7, 2016, and the only for the Little Elm Police Department.