America’s biggest coal miner, Murray Energy Corp., gave notice this week that it plans to lay off up to 4,400 workers in six states—roughly 80 percent of its workforce– in September.

Controlling owner Robert Murray did not mince words in his news release, blaming the forthcoming layoffs on “the ongoing destruction of the United States coal industry by President Obama, and his supporters, and the increased utilization of natural gas to generate electricity.”

Since Obama took office, the United States has lost 30,000 coal jobs, with the cuts falling especially hard in Wyoming, Illinois and Appalachia, the Wall Street Journal reported.

The mining sector fears that Hillary Clinton will continue the Obama administration’s anti-coal policies. Earlier this spring, she said she planned to “put a lot of coal miners and coal companies out of business,” a comment that has already cost her the support of many blue-collar traditional Democrats in West Virginia.

Clinton’s anti-coal stance has made a Trump supporter out of Murray, as the Wall Street Journal notes:

“Frankly, I am frightened for you, my employees, and the survival of your jobs and family livelihoods,” Mr. Murray told the crowd while introducing Mr. Trump, according to a copy of his prepared remarks. He added that electing “friends of coal” like Mr. Trump were the only hope the industry has.

Murray Energy Corp. isn’t the only coal mining company feeling the pain. In June, Wyoming’s Buckskin coal mine announced the elimination of 45 more positions. With those layoffs included, Wyoming’s Powder River Basin will have seen nearly 600 jobs lost this past year alone.