Students at Washington University in St. Louis started an outdoor sit-in on Tuesday night, calling for the school to cut its ties to Peabody Energy, a coal company, CBS News reported.

Dozens of students are pledging to camp out on campus until the University removes the coal company's CEO Gregory Boyce from the school's board of directors, CBS News reported.

The sit-in is being promoted with the help of Missourians Organizing for Reform and Empowerment (MORE), an activist group that has staged protests against Peabody Energy before over issues of pollution, global warming and the lack of health insurance for some coal miners.

"Personally, I'm a pre-med student and I'm studying to become a doctor to cure people who could potentially have their health problems affected by what Peabody works with," third-year student Nancy Yang told CBS News. "And I don't feel good about having the institution tied up like this."

Students also object to research that they say falsely suggests that the environmental issues associated with the use of coal can be minimized.

Washington University released a statement affirming the right of the students to protest, but defending research related to coal.

"We support our students' right and ability to express their opinions on the issue of coal or any other issue," school officials said. "We want our students to be motivated and engaged citizens and to develop into strong leaders."

School officials also said that "Washington University ... is a significant contributor to finding solutions to the world's energy challenges. Our researchers are focused on making alternative energy sources more viable."

Molly Gott, an organizer of the event and a member of MORE, told CBS News students are debating their next move, which could include picketing off-site at the Peabody Opera House, at their downtown headquarters, or at the Botanical Gardens.