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LITTLE ELM (CBSDFW.COM) – Investigators are giving a clearer picture of how everything unfolded when an armed suspect opened fire on Little Elm police, killing Detective Jerry Walker.

Police Chief Rodney Harrison spoke to reporters at a news conference at the Little Elm Town Hall, and sometimes struggled to keep his emotions under control. He was the last person to speak by radio to Detective Walker right before the suspect opened fire.

From the moment it all began Little Elm’s police chief and Detective Walker were aware of the seriousness of the call. Chief Harrison said Walker left his office to be one of the first to respond to the scene of a gunman outside a home, and Harrison arrived soon after.

“I was actually on the scene. I was less than 50 yards away. I saw Detective Walker get shot,” Harrison said.

Patrol officers made brief contact when they first arrived, but the suspect quickly barricaded himself inside the home. As a marksman observer for the SWAT team, Walker was trying to trace the first shot that came from inside the home.

“Moments later Detective Walker responded to me, ‘I think that he’s shooting at us,’ and then a hail of gunfire came from inside the residence in the direction of Detective Walker,” Harrison said.

Fellow officers returned fire and rushed Walker to the hospital where he later died. Harrison said it was several hours into the standoff that relatives of the gunman contacted police to let them know a woman believed to be the suspect’s grandmother was still inside the home.

Officers were able to rescue the woman from the back of the home unharmed. After that an armed vehicle smashed an opening into the front of the home allowing a robot to find the suspect dead inside. Now the chief said helping his department grieve is one of the toughest challenges.

“We have a police force of 51 officers, so you know everyone in our agency. You know their families, you know their kids. It makes it extremely difficult,” Harrison said.

The chief declined to identify the suspect. He said the Medical Examiner’s office is still conducting its investigation, and will release both the suspect’s name and cause of death at a later time.

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