The alleged incident occurred last spring at the upscale Hay-Adams Hotel, steps away from the White House, when Ignacio Zamora Jr. left a bullet from his gun inside a woman's hotel room, sources told ABC News.
Zamora, a supervisor, responsible for about two dozen agents in the presidential security detail, was off-duty and having drinks with the woman in the hotel when they ended up in her hotel room. The woman, according to sources, became uncomfortable when she saw Zamora had a firearm.
Zamora, sources said, disconnected the clip and removed a bullet to make sure she understood he was not a threat, but she was still uncomfortable. Zamora left the woman but left the bullet inside her room, the sources said.
Hotel Security apparently became aware of the encounter, sources said, and Zamora told them he left his wallet in the room. Security refused to let Zamora back into the room, but hotel officials recovered the bullet.
No police report was filed but hotel security informed the Secret Service about the incident, sources said. In the subsequent probe, investigators came across sexually suggestive emails that Zamora and another male Secret Service agent sent to a female agent. But sources say it could be viewed as innocent exchanges, given their long-term work acquaintance.
Zamora has been removed from the president's detail pending a final assessment. The other male agent, who ABC News is not naming, has not been removed from the president's security detail.
The Secret Service declined to comment about the allegations.
The Secret Service was embroiled in a prostitution scandal last year during preparations for Obama's trip to Cartagena, Colombia. Thirteen agents and officers were implicated after an agent argued with a prostitute over payment in a hotel hallway, pointing to a culture of carousing within the agency.