MONTPELIER, Vt. (AP) — A Vermont prosecutor who responded to the scene of a fatal shooting of a state social worker has resigned, citing post-traumatic stress disorder.

Washington County State's Attorney Scott Williams had been on health-related leave since Nov. 14. The state Department of State's Attorneys and Sheriffs announced his resignation Monday.

"The effect of the murder of Lara Sobel requires that I focus on regaining my health," Williams said in a statement. He said that despite his awareness of PTSD, he did not recognize his own health care needs and it was affecting his work performance.

Sobel was shot and killed as she left work on Aug. 7, 2015, by Jody Herring, who also killed three relatives.

Williams, who knew both Sobel and Herring, motioned for two men nearby to restrain Herring and then he disabled the rifle she had used, investigators said. He received a Carnegie medal for heroism.

The Times Argus reports that he's been under scrutiny recently for allegedly collecting money for a community fund that doesn't exist. Williams told the newspaper he tried to get a community fund started out of his office but after the shooting he was unable to make that happen and the contributions remain undeposited.

Barre City Police Chief Tim Bombardier, who has worked closely with Williams, praised him.

"Scott has served his country as a veteran, and this community and our county as a strong prosecutor, and he deserves to be well and happy," he said.

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