DALLAS (CN) - An assistant district attorney was shot to death Thursday east of Dallas in what colleagues believe was a work-related killing.
Mark Hasse, an assistant district attorney for Kaufman County, was killed by two masked gunmen, who fled.
Dallas County District Attorney Craig Watkins said this afternoon that an arrest had been made. But Watkins would not give any details, and Kaufman County officials "seemed unaware of any such arrest" at a 3 p.m. news conference, according to the Dallas Morning News.
"I can't overstep the bounds of Kaufman County," Watkins said, according to the Morning News. "All I can tell you is that there was an arrest."
The gunmen ambushed Hasse on his way to court and shot him repeatedly at about 8:50 a.m., radio station WFAA reported.
The courthouse and local schools were put on lockdown.
Hasse, 57, had been "heavily involved" in investigating the Aryan Brotherhood, the Morning News reported in an earlier story on the killing, attributing the information to "authorities with knowledge of the assistant DA's caseload."
Hours after Hasse was murdered today, two members of the Aryan Brotherhood pleaded guilty to federal racketeering charges, in a Texas case that Kaufman County prosecutors helped investigate, the Department of Justice said in a statement .
Colleagues described Hasse as "squeaky clean."
He joined the Kaufman County District Attorney's Office in July 2010.
An attorney told the Morning News that he arrived at the Kaufman County courthouse this morning just as police swarmed into it after the shooting. A shaken woman told the attorney she had seen the murder.
Kaufman County officials announced a $20,000 reward for information leading to conviction of the shooters.
Hasse was chief of the Dallas County District Attorney's organized crime section from 1985 to 1988 and was a former president of the Dallas chapter of Mothers Against Drunk Driving.
Kaufman County, pop. 104,000, is part of the Dallas-Fort Worth metroplex. Its seat is Kaufman.
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