KILLEEN, Texas — Editor's note: The video in this story is from Feb. 27, 2019.

A former Killeen police officer pleaded guilty Friday to tampering with evidence after a deadly shooting during the service of a no-knock warrant in February.  

Anthony Custance resigned after a Texas Rangers investigation into the shooting showed he didn't follow an operation's plan and he tampered with his rifle and ammunition.

Officers served a no-knock warrant at a home in the 200 block of West Hallmark Ave. on Feb. 27. Police killed James Reed, a known drug dealer, while serving the warrant.

RELATED: Officer-involved shooting: Former Killeen police officer charged after investigation shows tampering of evidence

The Texas Rangers' investigation showed Custance fired into the back of the home where Reed was. Although the rounds didn't cause injuries, Custance did not follow the Killeen Police Department's plan for serving the no-knock warrant, investigators said.

The investigation also showed that Custance tried to hide a rifle magazine with missing rounds, according to an affidavit. Custance showed Texas Rangers a 30-capacity rifle magazine loaded with 28 rounds "with knowledge of its falsity and with intent to affect the course or outcome of the investigation," the affidavit said.

RELATED: Man identified in deadly officer-involved shooting in Killeen was known drug dealer, 'always armed,' police say

Once the department started an internal investigation into Custance's actions, he resigned.

Custance is expected in court for sentencing for the third-degree felony on Dec. 3.

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