Martin Shkreli, the notorious, price-gouging "pharma bro" who became a widely despised symbol for soaring drug prices earlier this year, was arrested by the FBI on Thursday after a federal investigation involving his former hedge fund and a pharmaceutical company he previously headed.

Shkreli, 32, sparked national outrage in the US earlier this year after his pharmaceutical company, Turing Pharmaceuticals Inc, hiked the price of the drug Daraprim, a common anti-parasitic drug, to $750 a tablet from $13.50 immediately after acquiring it. Shkreli staunchly defended his decision, responding "lol" to Hillary Clinton on Twitter after she criticized him.

Shkreli's arrest Thursday comes after a fraud investigation stemming from his time as manager of hedge fund MSMB Capital Management and CEO of biopharmaceutical company Retrophin Inc, a person familiar with the matter said.

Reuters witnessed law enforcement agents arresting a hoodie-clad Shkreli at the Murray Hill Tower Apartments and escorting him into a car in midtown Manhattan today. A spokesperson for the FBI confirmed Shkreli's arrest.

Shrekli is expected to be charged today for illegally using assets from Retrophin to pay off debts after his hedge fund lost millions of dollars, the source said.

The probe dates back to at least January when Retrophin said it received a subpoena from prosecutors seeking information about its relationship with Shkreli.

Shares of Shkreli's pharmaceutical company, KaloBios Inc, fell by about 50 percent to $11.03 in premarket trading. His stake in the company plummeted by more than $25 million in value between Wednesday and when news of his arrest broke today, noted Market Watch.

In addition to angering pharmaceutical executives and consumers alike, Shkreli has also managed to piss off hip-hop fans too. He recently bought the sole copy of Wu-Tang Clan's latest album, Once Upon A Time In Shaolin, for $2 million after the rap group agreed to sell it to the highest bidder. He then threatened to destroy the CD.

Lawyers for Retrophin and Shkreli did not immediately respond to a request for comment. Turing and KaloBios declined to comment.