Climate change is responsible for the death toll of Sunday’s tornado that ripped through Lee County and killed at least 23 people, Sen. Bernie Sanders suggested in a Facebook post.

“The science is clear, climate change is making extreme weather events, including tornadoes, worse,” the independent Vermont senator said in a Facebook post linking to an EcoWatch article on the tornado. “We must prepare for the impacts of climate change that we know are coming. The full resources of the federal government must be provided to these families. Our thoughts are with the people of Alabama and their families.”

The EcoWatch story cited a climate researcher who said the tornado bolstered the opinion that so-called “tornado alley” in Texas, Oklahoma, Kansas and Nebraska is moving east.

“It’s not a big jump to say that climate change is causing this shift east," Dr. Victor Gensini of Northern Illinois University, the author of a study cited in the story, told CBS News. “The hypothesis and computer simulations support what we are observing and what we expect in the future.”