WACO, Texas (CBSDFW.COM/AP) — Prosecutors have dismissed another 42 cases relating to the 2015 shooting in Waco involving rival biker gangs that left nine people dead and 20 others injured.

McLennan County prosecutors said Tuesday they’re dismissing the cases while focusing on “more culpable” defendants.

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Waco bikers after shooting

About 130 cases have been dismissed or refused for prosecution since February and officials said in late April that only about 25 cases will be prosecuted out of the more than 150 people indicted on felony charges of engaging in organized criminal activity.

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Police arrested 177 bikers following the mayhem at a Twin Peaks restaurant involving members of the Bandidos and Cossacks motorcycle clubs.

Waco police officers monitoring the gathering also fired on the bikers, killing two.

Only one biker has ever been tried and it ended in a mistrial.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)