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Updated at 7:24 p.m. ET: An assistant district attorney in Texas was gunned down Thursday morning in what appears to be a targeted attack, police say.
Kaufman County Assistant District Attorney Mark Hasse was shot multiple times while walking from the parking lot toward the county courthouse at about 8 a.m. local time, officials said. He was transported to a nearby hospital where he later died.
When asked if Hasse appeared to have been targeted by his attacker, Kaufman County Sheriff David Byrnes said, "I would say from all appearances it is. But we have no concrete information on that. We're pursuing every avenue right now."
Authorities investigate the Kaufman County Tax Office drive-thru after a deadly shooting on Thursday.
"We suffered a devastating loss today. We lost a really, really good man. He was an excellent friend and a spectacular prosecutor. He will not be easily replaced. He will be sorely missed by everybody in the office," said Kaufman County Criminal District Attorney Mike McLelland. "I hope that the people that did this are watching because we are very confident that we are going to find you, pull you out of whatever hole you're in, bring you back and let the people of Kaufman County prosecute you to the fullest extent of the law."
Chris Aulbaugh, the Kaufman Chief of Police, said no official arrests have been made in connection with the shooting but that they are following up on several leads, including multiple witness reports from various angles around the crime scene.
Agents with the ATF, FBI, the Texas Rangers and State Troopers from the Texas Department of Public Safety are at the scene assisting local and county law enforcement with the investigation.
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Police said witnesses have reported two shooters wearing all black, one or both of them possibly wearing a tactical-type vest, and driving an older, silver Ford Taurus. Aulbaugh said they have not yet confirmed that there were two people involved in the shooting and if the shooter(s) were wearing a tactical jacket as described.
Police taped off the parking lot near the Tax Assessor/Collectors office, which is near the courthouse and is commonly used by judges and prosecutors. Officers later expanded the taped-off area to include two city blocks. Several streets around the courthouse and parking lot are closed as the shooting is investigated.
Investigators said they were not aware of any threats made toward Hasse and that they didn't know of any cases that might explain the shooting, but that Hasse was aware of the dangers associated with his profession.
"Mark was fully aware of the dangers of this job. He accepted them readily and was, as I said before, an absolutely stellar prosecutor and good friend," said McLelland. "Tell the people that they have lost an outstanding man who will not be easily replaced."
Eric Smenner, a friend of Hasse's, told NBC 5's Scott Gordon that while it was too soon to say what may have led to the shooting, Hasse had dealt with cases involving methamphetamine in the county, gangs and white supremacist groups. He described Hasse as a hard-working lawyer who "loved to tell stories" and often put dangerous criminals behind bars.
Tonya Radcliffe, a board member on the Kaufman County Appraisal District whose office is adjacent to the scene of the shooting, said a staff member heard the gunshots and called police. Radcliffe said she and her staff of about 25 are in the building and under lockdown.
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During the early stages of the investigation, a hospital, several schools and county buildings, including the Tax Assessor/Collector's office, were locked down as a precaution. With Thursday being the last day for people to pay property taxes without a penalty, officials advised Kaufman County residents that they could still pay taxes using the county's pay by phone option or make payments in person at sub-courthouses and drop boxes.
A 36,000 reward for information leading to the arrest and conviction of the gunman is being offered with $10,000 coming from Kaufman County Crime Stoppers, $10,000 from a local Kaufman business and donations continue to pour in from local businesses. As always, tipsters may remain anonymous.
Anyone with information is asked to call Kaufman County Crime Stoppers at 1-877-TIPS-KCC.
NBCDFW.com Editor's Note: Greenville ISD was under lockdown due to a search for robbery suspects. The lockdown was not related to the Kaufman County shooting.
NBC 5's Randy McIlwain, Scott Gordon, Ken Kalthoff, Keaton Fox and Deborah Ferguson contributed to this report.