Residents of the Sharpless Works Apartments at 300 East Evans Street were asked to leave their homes around 8:45 a.m., WCPD Public Information Officer Dave March said.
"Crews continue to investigate the source of the incident," March said in an update around 10 a.m. "Those who have been evacuated are safe in an air-conditioned site."
By 11:15 a.m., emergency crews had cleared the scene and turned control of the site over to "management and an environmental service agency."
"The source of the incident was located," March said. "Most of those evacuated will be returning home, those who can not will be relocated to different apartments for the time being."
Officials did not describe the "incident" in detail but said, "there is no further threat to the public."
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