The Harris County Sheriff's Office has confirmed the death of a deputy constable who was shot ambusth-style in a parking lot in the Texas city of Baytown early Monday morning. The officer was later identified as 30-year veteran Assistant Chief Deputy Clinton Greenwood. The gunman had not been apprehended as of late Monday morning.

Investigators said the unidentified suspect opened fire at around 7 a.m. local time, according to the Baytown Sun. The shooting took place near an unmarked police SUV parked outside the county clerk's office, KHOU-TV reported. Greenwood was shot in the neck and called for help over the dispatcher saying “I’m bleeding out,” according to KTRK-TV.

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A nearby deputy came to Greenwood's aid and began applying pressure to his neck immediately. 

Greenwood was then airlifted to a Texas Medical Center in Houston, where he was later pronounced dead.

It was not clear whether Greenwood was deliberately targeted, as he was shot from a distance. It was also unclear what prompted the shooting.

To date, the courthouse and neighboring Sterling High School is on lockdown due to the proximity of the shooting, according to Goose Creek CISD.

"to police activity in the area, RSS is in lockdown. Students are safe. There has not been an event on campus. There will be a 2 hour delay to the start of school. If your student is not already on campus, please do not bring them to school until further notice. We will update as we have more information," Goose Creek CISD wrote on their Facebook page minutes after the shooting. 

Police said they were investigating Monday's incident and were searching for the suspect, although no description has yet been released. 

"What I can tell you is we have the full force of the Baytown Police Department working on the case along with members from the Harris County Sheriff’s Department, the Texas Rangers, the Pct. 3 Constable’s Department and the Gulf Coast Violent Offenders Task Force," Lt. Steve Dorris with Baytown Police Department said during Monday’s press conference.  

This is a breaking news story and will be updated as additional information becomes available.