SAN ANTONIO (CBSDFW.COM/AP) – A San Antonio police officer will not face criminal charges for fatally shooting an 18-year-old, who authorities say was hit by gunfire aimed at someone else.

Prosecutors announced Thursday, a grand jury voted not to indict San Antonio Officer Steve Casanova for the 2018 death of Charles Roundtree, Jr.

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Casanova shot Roundtree after arriving at a San Antonio home to investigate a reported assault.

Police have said the officer opened fire when another man, Davante Snowden, reached for a gun.

Roundtree’s mother is suing the city of San Antonio, and says no one in the home was armed.

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Attorney Daryl Washington says Roundtree’s family is “extremely disappointed” in the grand jury’s decision.

The Bexar County District Attorney’s Office says Snowden is facing a gun charge connected to the incident.

So far, the San Antonio Police Department declined to comment.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)