WASHINGTON (AP) - Environmental Protection Agency chief Scott Pruitt, yet another Trump administration official with his job on the line over ethical concerns, took heat from lawmakers Thursday over his profligate spending and lobbyist ties and tried to divert responsibility to underlings.

The EPA administrator said "twisted" allegations against him were meant to undermine the administration's anti-regulatory agenda, and he denied knowing details of some of the extraordinary spending done on his behalf at the agency.

The public grilling at back-to-back House hearings, called formally to consider EPA's budget, came as support has appeared to erode for Pruitt among fellow Republicans after revelations about unusual security spending, first-class flights, a sweetheart condo lease and more. Even Republicans who heartily support Pruitt's policy agenda said his apparent lapses had to be scrutinized.

Democrats excoriated him.

"You are unfit to hold public office," said Rep. Frank Pallone of New Jersey.

"You've become the poster child for the abuse of public trust," said Rep. John Sarbanes of Maryland.

Although some Republicans rallied around Pruitt, reviews were mixed. Rep. John Shimkus of Illinois, chairman of the first panel that questioned Pruitt, said afterward the EPA chief was "a little vague," adding, "It's never a good idea to blame your staff in public."

Asked whether Pruitt should resign, he said that's not his call and suggested that's up to President Donald Trump.

Pruitt gave clipped, bureaucratic answers to questions on the many financial allegations against him, relaxing when Republicans on the panel gave him openings to expand on his policy steps at EPA.

Mocking Pruitt's opponents, Republican Rep. Kevin Cramer of North Dakota said that as far as the EPA chief's critics were concerned, "I think the greatest sin you've done is you've actually done what President Trump ran on."

"It's shameful that this day has turned into a personal attack," said GOP Rep. Bill Johnson of Ohio.

Trump has stood by his EPA chief, but behind closed doors, White House officials concede Pruitt's job is in serious jeopardy.

Pruitt has faced a steady trickle of revelations involving 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 chief acknowledged under sharp questioning that he, in fact, knew something about huge pay raises given to two women on his staff - at least one of them a friend - after insisting weeks ago that he didn't approve the raises and didn't know who did. After that initial denial, documents showed EPA chief of staff Ryan Jackson signed off on the raises and indicated he had Pruitt's consent.

Pruitt said Thursday he actually delegated authority to Jackson to give the raises but didn't know the exact amounts. Senior legal counsel Sarah Greenwalt received a raise of more than $66,000, bringing her salary to $164,200, and scheduling director Millian Hupp saw her salary jump from $48,000 to $114,590.

As he has previously, Pruitt sought to deflect questions about any missteps by blaming subordinates.

- On the communications booth: "I was not involved in the approval of the $43,000, and if I had known about it, Congressman, I would not have approved it."

- On flying first class at taxpayer expense: "Security decisions at the agency are made by law enforcement personnel, and I have heeded their counsel."

- On the pay raises to the two women: "I was not aware of the amount provided or the process that was used in providing that."

At several points, he spoke of decisions made by "career individuals at the agency."

"You're the guy in charge," Democratic Rep. Peter Welch of Vermont countered. "It really seems like there's something on your desk with the motto: 'The buck stops nowhere.'"

Pruitt drew an unusual rebuke from EPA's inspector general, Arthur Elkins, while he was still testifying. In a statement, Elkins said he never signed off on an internal review of security threats that Pruitt cited at the hearing to explain why he needed unusual arrangements for his safety.

Elkins said the summary was prepared by Patrick Sullivan, an assistant inspector general, and "leaked without authorization."

Pruitt read aloud from two security threats, one from a man, apparently in India, who tweeted that he planned to shoot Pruitt.

Democratic Rep. Betty McCollum of Minnesota was unmoved, saying: "We all receive threats on our Facebook page."

Pruitt's troubles began in earnest last month, when ABC News first reported he had leased a Capitol Hill condo last year for just $50 a night that was co-owned by the wife of a veteran fossil fuels lobbyist whose firm had sought regulatory rollbacks from EPA.

Both Pruitt and the lobbyist, Steven Hart, denied he 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 firm, Williams & Jensen, revealed he had lobbied the agency on a required federal disclosure form.

Under questioning, Pruitt acknowledged that Hupp, the scheduling director whose pay soared, helped him find accommodations in the capital but said her search apparently did not cost taxpayers. "I'm not aware of any government time being used," he said. "She is a friend."

Thursday's hearings were Pruitt's first major appearance since a Fox News interview in early April that was widely considered to be disastrous within the West Wing.

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