Big Coal is coming for John Oliver. In response to the most recent episode of Last Week Tonight, Murray Energies magnate Robert Murray has filed a defamation lawsuit alleging the "false and malicious broadcast" amounted to "ruthless character assassination" of the 77-year-old coal baron. The suit also takes aim at the show's supposed partisanship, which "vigorously supported and advanced Mrs. Clinton's agenda," according to the complaint.

The June 18th segment (below) was focused on President Trump's false promise to coal miners, but the comedian also spent a good chunk of the segment lambasting the so-called King of Coal—or "geriatric Dr. Evil," in Oliver's words—over his treatment of employees. According to Oliver, Murray Energies is to blame for a mine that collapsed in Utah in 2007, killing nine people. While the coal baron maintains that the collapse was caused by an earthquake, government research concluded the tragedy was the result of "unauthorized mining practices."

That incident is at the root of the lawsuit, which claims that Oliver and his producers "ignored facts in their possession that directly contradict the false and defamatory statements" made about the mine collapse. Murray had been made aware of the segment before it aired, and sent both a cease and desist letter and his own research to Last Week Tonight in anticipation of the episode.

Parts of that letter were shared with the audience by Oliver, who also said that he was expecting to be sued for the segment. "Bob Murray, I didn’t really plan for so much of this piece to be about you, but you kinda forced my hand on that one,” he said on during the segment. “And I know you’re probably going to sue me over this. But, you know what? I stand by everything I said."

Later on in the episode, Oliver brought out a man in a giant squirrel costume, a reference to Murray's alleged claim that a squirrel told him to start a mining company (Murray denies this). "Bob, I just wanted to say if you plan on suing, I do not have a billion dollars, but I do have a check for three acorns and 18 cents," the squirrel said. "It's made out to 'Eat sh*t Bob!"

In addition to Oliver, the suit names HBO, Time Warner, and Last Week Tonight's Senior News Producer Charles Wilson for one count each of defamation, false light invasion of privacy and intentional infliction of emotional distress.

In a statement, HBO said that they were not concerned by the lawsuit: "While we have not seen the complaint, we have confidence in the staff of Last Week Tonight and do not believe anything in the show this week violated Mr. Murray's or Murray Energy's rights."