A group of congressional Democrats have called for an investigation after reports emerged that Health and Human Services Secretary Tom Price took five official business trips on private jets in lieu of commercial flights last week, at an estimated cost of at least $60,000, said reports.

The original report from Politico on Tuesday said internal documents of the HHS department stated the trips took place between Sept. 13 and 15 to Maine, where he participated in a Q&A discussion with a health care industry CEO, and to community health centers in New Hampshire and Pennsylvania.

The report also said the expenses for the travel were not paid by the health groups that had invited Price, suggesting that the money might be taxpayer dollars.

The net worth of the former orthopedic surgeon who is a part of Trump’s billion dollar cabinet was said to be just over $13.6 million as of 2014, according to the Center for Responsive Politics.

An article in Forbes from December 2016, however, put his net worth as $10 million. According to Forbes, the congressman owned a medical office building in his home state, plus rental apartments and condos in Virginia, Washington, D.C., North Carolina, South Carolina and Tennessee.

Price also had a hefty stock portfolio with investments in pharmaceutical, medical device, and health insurance companies.

He had promised to sell his medical stocks if confirmed as Trump’s health chief in order to avoid conflict of interest. He also made money by selling the stocks he held in an Australian biotech firm, which had become the subject of intense interest after Democrats raised concerns of insider trading against it.

The congressman was ranked the 50th richest member of Congress  by the Capitol Hill publication Roll Call.

Tuesday’s report landed Price in hot water and some pointed to his 2009 interview with CNBC in which he can be seen arguing against congressional expenditures in millions of dollars for several private planes that would transport members of Congress. 

"This is just another example of fiscal irresponsibility run amok in Congress right now," he said.

However, an unnamed HHS spokesperson told Politico that Price sometimes chose private travel because commercial options were impractical.

"As part of the HHS mission to enhance and protect the health and well-being of the American people, Secretary Price travels on occasion outside Washington to meet face to face with the American people to hear their thoughts and concerns firsthand," the spokesperson said. "When commercial aircraft cannot reasonably accommodate travel requirements, charter aircraft can be used for official travel."

Meanwhile, the group of Democrats led by Rep. Frank Pallone Jr. (D-N.J), the ranking member on the Energy and Commerce Committee, wrote to the HHS Office of the Inspector General on Wednesday. 

"American taxpayers deserve assurances that their tax dollars are not wasted by the government's highest officials, and we are committed to holding Secretary Price to his stated pledges to reduce waste throughout the Department. Therefore, we appreciate your prompt and thorough review of these issues," the Democrats wrote.