Martin Shkreli smirked as Rep. Elijah Cummings berated the former drug CEO for operating a Ponzi-like scheme.

"It's not funny Mr. Shkreli," Cummings snapped at a House Oversight Committee hearing on Thursday. "People are dying and they're getting sicker and sicker."

Shkreli's smirk remained.

Cummings said Turing Pharmaceuticals, which Shkreli used to run, had been dealing in "blood money." By hiking up the price of Daraprim, a toxoplasmosis treatment used by AIDS patients, by 5000%, Cummings said that Shkreli was taking advantage of Turing's customers.

"Like a Ponzi scheme, it appears that Turing might be using profits from Daraprim to invest in new drugs that it would then jack up prices for," Cummings said.

Cummings also lashed out at the former CEO for his lavish spending, on the back of the hiked-up drug prices. He cited Shkreli's famous $2 million purchase of the Wu-Tang Clan's single pressing of its new album, "Once Upon a Time in Shaolin."

"My constituents. They don't buy Wu-Tang Clan albums," Cummings said. "They live paycheck to paycheck."

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Shkreli did not give testimony.

"On the advice of counsel, I invoke my Fifth Amendment privilege against self-incrimination and respectfully decline to answer your question," Shkreli said repeatedly.

Shrkeli rolled his eyes during questioning, fiddling with his pencil and refusing to look at the committee members.

I had prior counsel produce a memo on facial expressions during congressional testimony if anyone wants to see it. Interesting precedence. — Martin Shkreli (@MartinShkreli) February 4, 2016

The hearing briefly turned into a bit of orchestrated theater. Rep. Trey Gowdy tried to get an answer out of Shkreli and briefly succeeded when he asked him about the pronunciation of his name. Gowdy then asked several questions about the Wu-Tang Clan album, goading Shkreli to answer questions that he believed the Fifth Amendment did not shield him from.

At one point, Ben Brafman, Shkreli's lawyer, stood up and demanded that the line of questioning stop.

Committee Chairman Jason Chaffetz quickly put an end to the circus by demanding that Brafman sit down. He eventually excused Shkreli from the hearing and said he did not intend to hold Shkreli in contempt.

Nancy Retzlaff, Turing's chief commercial officer, testified at the hearing that the hiked prices didn't affect customers, most of whom paid a penny per pill.

Outside the hearing room, Brafman held a brief press conference, in which he said it was "extraordinarily unfair" that Shkreli had been singled out, calling him a "hero."

Brafman said that Shkreli had badly wanted to answer Congress' questions but instead followed his advice to refuse testimony.

Shkreli took to Twitter immediately after the hearing, tweeting that it was "hard to accept that these imbeciles represent the people in our government."

Hard to accept that these imbeciles represent the people in our government. — Martin Shkreli (@MartinShkreli) February 4, 2016

In January, Shkreli tweeted a photo of a subpoena he received to appear before the House oversight committee. He questioned whether to attend the hearing on "developments in the prescription drug market."

Shkreli also opted to plead the Fifth after receiving a subpoena from the Senate Committee on Aging.

Committee Chairwoman Senator Susan Collins tweeted that Shkreli's actions could impede Congress' investigation, absent a valid justification. But Shkreli defended his constitutional right to plead the Fifth.

Shkreli is also facing securities fraud charges involving Retrophin (RTRX), another biotech company that he ran several years ago. He recently replaced his attorney in that case and is next scheduled to appear in federal court on May 3.