Updated at 5:30 p.m. ET

Environmental Protection Agency Administrator Scott Pruitt, already battling roughly a dozen ethics investigations, allegedly asked a top aide to obtain a used mattress from President Trump's Washington, D.C., hotel.

Millan Hupp, Pruitt's director of scheduling and advance, told House investigators last month that she couldn't track down the mattress, and didn't know if Pruitt ultimately got one.

A spokeswoman for the Trump International Hotel had no comment on any aspect of the story.

As Hupp recounted it for the committee staff, "The administrator had spoken with someone at the Trump Hotel who had indicated that there could be a mattress that he could purchase, an old mattress that he could purchase."

An investigator allowed, "It sounds like an odd conversation."

A transcript of segments of the lengthy interview, released by committee Democrats, quotes Hupp as saying she didn't know why Pruitt wanted the used mattress. But she said the mattress project came when Pruitt and his wife were apartment hunting, and Hupp was helping them.

Hupp's involvement would seem to violate federal ethics rules, which prohibit federal workers from doing private work for their superiors.

Hupp said she contacted agents and toured properties on the Pruitts' behalf over a couple months, usually during her lunch hours. She recounted how one agent found them an apartment, but after moving in, the Pruitts decided they weren't comfortable in the neighborhood. The Pruitts negotiated an end to the lease, and Hupp resumed her search.

Hupp also said she booked Pruitt a flight to the Rose Bowl, using her vacation time and his personal credit card.

Pruitt is under scrutiny by the EPA Inspector General, Congress's Government Accountability Office, and several congressional panels on a range of issues. He's stopped flying first class, which violated government standards, but has used lobbyists to arrange trips. He had a $43,000 soundproof booth built in his office, and got a sweetheart deal on a temporary apartment from the wife of an EPA lobbyist. He also allegedly retaliated against EPA whistleblowers who reported ethics problems.

Hupp was interviewed by Republican and Democratic staffers on the House Oversight and Government Reform Committee. The committee's top Democrat,
Rep. Elijah Cummings, D-Md., and Rep. Gerald Connolly, D-Va., top Democrat on its Government Operations subcommittee, today asked committee chairman Trey Gowdy to subpoena more documents about Hupp's work for Pruitt.

Cummings and Connolly wrote it appears that Pruitt "crossed a very clear line and must be held accountable."

EPA spokesman Jahan Wilcox said in a written statement that Pruitt's office is "working diligently with Chairman Gowdy" and is in "full cooperation" in providing documents to House Oversight.

When asked by reporters during Monday's White House press briefing, press secretary Sarah Sanders said the administration was "looking into the matter" but that she "couldn't comment on the specifics of the furniture used in his apartment."

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