The Yale-Harvard football game on Saturday was disrupted by climate protesters storming the field during halftime to demand that the two Ivy League universities divest from fossil fuels.

Photos shared on social media show a large crowd sitting on the field at Yale Bowl in New Haven, Connecticut, while others stand behind them with a large sign that read: "Nobody Wins: Yale & Harvard are complicit in climate injustice."

Another sign read: "Yale and Harvard students united for climate justice"

Divest Harvard — a group that advocates for the Massachusetts university to divest its endowment holdings in the fossil fuel industry — said in a tweet that more than 150 Yale and Harvard students, alumni, and faculty rushed onto the field to "demand DIVESTMENT from fossil fuels & cancel holdings in Puerto Rico debt."

Advocate group Fossil Free Yale tweeted that the two prestigious universities "have no right to profit off the destruction of the planet and land."

The students sat in the middle of the field and delayed the start of the second half by at least 45 minutes, NBC Connecticut reported.

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Initially, about 40 to 50 students rushed the field and staged a sit in at the 50-yard line, according to NBC Connecticut. Another 500 or so joined in a short time later, but quickly dispersed. The original protesters remained on the field, until police and security officials began to clear them.

The protests led to some celebrity support.

"I’m proud to support the students of @DivestHarvard and @FossilFreeYale who disrupted #HarvardYale today to call for fossil fuel divestment," actress Alyssa Milano wrote on Twitter. "When our richest universities are invested in the destruction of the planet #NobodyWins."

Actress Daryl Hannah congratulated the student activists and called on Yale and Harvard "to divest." "When it comes to the further destruction of our planet #nobodywins," she tweeted.

Yale University said in a statement that while it "stands firmly for the right to free expression," it was "regrettable that the orchestrated protest came during a time when fellow students were participating in a collegiate career-defining contest.”

"We are grateful to the staff members and police officers who ensured the peaceful departure of students from the field," the school added. "The exercise of free expression on campus is subject to general conditions, and we do not allow disruption of university events."

Once the game resumed, Yale rallied for a thrilling 50-43 overtime victory. By winning the match with Harvard, known as "The Game," Yale earned a share of the Ivy League title with Dartmouth College.