The Environmental Protection Agency's watchdog confirmed in a letter this week that it is looking into multiple allegations leveled against EPA chief Scott Pruitt.

The letter, sent from EPA Inspector General Arthur Elkins, Jr., to Rep. Ted Lieu, D-Calif., confirmed it is already reviewing, or will be reviewing a number of misconduct claims against Pruitt. Lieu had asked the OIG to look into the housing arrangement Pruitt had with a condo connected to a lobbyist, expenses for his travel, expenditures for security measures and personnel, the EPA approvals of hiring and salaries for certain employees, the use of Pruitt's subordinates' time, and any reassignments or demotions of staff members who raised concerns about any of those issues.

Pruitt's $50-a-night condo deal, his previous use of expensive air travel and other things have prompted negative headlines about the EPA chief for weeks. Lieu wrote the OIG requesting him to look into such matters on April 3. The Office of Government Ethics, which is the government's main ethics watchdog agency, and lawmakers had asked for investigations of the condo lease and others of the latest allegations raised involving Pruitt. The agency's whistleblower hotline also had received calls on the same allegations, Elkins wrote. Pruitt's condo deal would not be overlooked as the OIG probes multiple allegations, Elkins suggested.

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"We have received multiple requests from multiple members of Congress, as well as other OIG Hotline complaints, regarding these same and related issues," Elkins wrote to Lieu. " After considering the OG request, the DAEo's referral to the OIG, your request as well as other congressional requests and the other Hotline complaints, the OIG has concluded that it will review the matters enumerated above. The matters include issues you have raised to the OIG in your letter of April 3, 2018."

EPA spokesman Jahan Wilcox declined comment Friday, saying the agency does not publicly address matters related to the inspector general.

Pruitt for much of last year rented a Washington bedroom from a lobbyist whose husband had pending matters before the EPA. The unusual deal allowed the EPA chief to pay just $50 a night, and only on the nights he actually stayed there.

Both Pruitt and the lobbyist, Steven Hart, denied Hart had conducted any recent business with EPA. But Hart was forced to admit last week he had met with Pruitt at EPA headquarters last summer after his then-firm, Williams & Jensen, revealed he had lobbied the agency on a required federal disclosure form

Announcement of the new investigations comes a day after Pruitt weathered six hours of scathing questions and criticism from House Democrats on ethics allegations, in back-to-back hearings.

The hearings were seen as make-or-break for Pruitt in the wake of months of news reports into alleged misconduct that eroded support of the former Oklahoma attorney general at the White House.

Pruitt gave clipped, lawyerly answers to Democrat's questions on the ethics allegations on Thursday, repeatedly blaming subordinates for decisions he said he had no knowledge of.

The day ended without any obvious, immediate mortal blow to Pruitt politically, and no Republican lawmakers in the hearings joined calls on Pruitt to resign.

"He obviously hopes that the bad headlines generated by his bad behavior will go away, and that he won't be held accountable for his actions," said Rep. Don Beyer, a Virginia Democrat and one of the members of Congress asking for the expanded probes.

"The Inspector General's letter announcing new reviews assures us that this will not happen," Beyer said in a statement.

Pruitt is a onetime Oklahoma state lawmaker who built alliances to wealthy oilmen and influential Republican conservatives. As head of the environmental agency he has faced an unending series of revelations involving issues such as pricey trips in first-class seats and unusual security spending, including a $43,000 soundproof booth for making private phone calls.

He also demanded 24-hour-a-day protection from armed officers, resulting in a 20-member security detail that blew through overtime budgets and racked up expenses approaching $3 million.

The EPA's inspector-general, the Government Accountability Office and the White House Office of Management and Budget all have announced probes into several of the earlier allegations.

Besides Pruitt's housing arrangements, Elkins' letter indicated new or expanded investigations into more recent allegations about Pruitt's spending on travel and security; claims that he gave two favored staffers big raises despite White House opposition; and claims that he assigned one staffer to help him hunt for a house in Washington. Investigators also would look into news reports that the EPA punished staffers who went public with complaints about Pruitt's spending, Elkins indicated.

Pruitt denied wrongdoing in his testimony to lawmakers on Thursday, and denied knowledge of any rule-breaking in either raises or demotions.