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HOUSTON (AP) — A law enforcement commander told thousands of mourners that a Houston-area deputy constable who was shot to death this week “was always the smartest guy in the room.”

Montgomery County Sheriff’s Lt. Tim Cannon said Thursday during a funeral service in Houston that Clint Greenwood was a consummate professional, meticulous with details and the first to lend colleagues a hand.

The 57-year-old Greenwood, a Harris County assistant chief deputy constable, was killed Monday by a gunman who stepped out from behind a trash bin as Greenwood arrived for work at a sub-courthouse in Baytown, east of Houston.

No arrest has been made, but Baytown police released a surveillance video Thursday that shows a possible suspect near the scene and the man’s car — a black 2013-2017 Nissan Versa Note.

The video shows the otherwise empty sub-courthouse parking lot Sunday afternoon, the day before Greenwood was fatally shot, said Lt. Steve Dorris, the Baytown police spokesman. The car passes in front of the surveillance camera and parks, then a man steps out and walks out of view. Moments later, the man returns to the car and drives away.

“The natural thought is that he was doing some pre-operational planning,” Dorris said.

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