Washington (CNN) The former head of human resources at the Federal Emergency Management Agency, Corey Coleman, has been accused of trading sex for jobs at the agency, according to a source with knowledge of FEMA's internal investigation into the matter and an executive summary of the preliminary findings of the investigation.

An executive summary of the preliminary investigation reviewed by CNN finds that Coleman engaged in sexual relationships with female subordinates. In the report, witnesses accuse him of pressuring the women and demoting them when they tried to deny his advances, intimidating staff and creating a toxic work environment.

Coleman's name does not appear in the executive summary, but the source confirmed he is the subject of the report.

Investigators allege that when Coleman was approached for an interview, he resigned. The source said the resignation occurred on June 18.

"Results of a recent internal investigation concerning allegations of sexual misconduct against the former Chief Component Human Capital Officer leave me no choice but to take decisive action to address lapses in professional responsibility, including requesting further investigation by the DHS Office of the Inspector General," FEMA Administrator Brock Long said in a statement. "These allegations are deeply disturbing and harassment of any kind will not be tolerated at FEMA."

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