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DALLAS (CBSDFW.COM/AP) — Dallas police Chief David Brown, who oversaw the response to a July sniper attack that killed five officers, is moving up his retirement date.

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Brown released a statement Thursday saying he’s moving up the date to Oct. 4 to take advantage of some “time sensitive opportunities.” He didn’t elaborate:

I have moved my retirement date up to October 4, 2016 in order to take advantage of some time sensitive opportunities that have been presented. I am confident that a strong leadership succession plan is already in place for the department and I feel comfortable in accelerating my departure date. Again, I want to thank all of the officers of the Dallas Police Department for your hard work and sacrifice that has made my job easier throughout the years. Thank you and God bless!

The chief previously said he would step down Oct. 22 — his 56th birthday.

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Brown is retiring after 33 years as a Dallas officer and six years as chief.

Arguably his defining moment leading the department was his impassioned response to the July 7 fatal shootings of four Dallas officers and one transit officer as a downtown protest against police brutality was ending.

But he’s also drawn criticism from unions for not doing enough to retain officers.

Assistant Chief David Pughes will serve as Interim Police Chief when Brown departs.

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