A report earlier this month was sharply critical of Thomas' "slow-footed response" as the violence began to escalate around Emancipation Park on August 12. That same day, a woman was killed when a car plowed into a crowd after the rally was declared an unlawful assembly.
The report also said Thomas deleted text messages and made officers fearful for speaking with investigators.
Activist Don Gathers said he is upset with the announcement: "It's sad and I hope that no one loses the irony of the fact that a black man is being forced out of office because of a white supremacist rally. And for him to be the only one being made to fall on the sword, it's sickening. It's just not proper," he said.
Gather added, "We need to put some of this at the mayor's doorstep, because he failed to guard the city in a proper way. There's so much blame to be spread around, and what the city is done today is something I didn't think was possible: they have further divided an already fractured city and it just can't stop here. It can't end here."
An attorney for Thomas said the chief disputes that he deleted text messages.
Thomas' secretary said he is not available for a comment on his departure.
Charlottesville said it will immediately begin the search for a new police chief.
12/18/2017 Release from Charlottesville:
CHARLOTTESVILLE, VA - Charlottesville Police Chief Alfred Thomas announced his retirement today after 27 years of law enforcement service. His retirement is effective immediately.
A veteran of the United States Air Force, Thomas was appointed police chief in April of 2016 and began his service one month later on May 23rd.
"Nothing in my career has brought me more pride than serving as the police chief for the city of Charlottesville," said Thomas. "I will be forever grateful for having had the opportunity to protect and serve a community I love so dearly. It truly has been an unparalleled privilege to work alongside such a dedicated and professional team of public servants. I wish them and the citizens of Charlottesville the very best."
"Chief Thomas has served his country and three communities here in Virginia with distinction and honor," said City Manager Maurice Jones. "He is a man of integrity who has provided critical leadership for our department since his arrival. We wish him all the best in his future endeavors."
Mr. Jones will formally appoint an interim police chief within the next week. Deputy Chief Gary Pleasants will guide the department until the interim chief is appointed.
The city will begin its search for a new chief immediately.
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