Climate protesters brought a U.S. Open semifinal match to a halt on Thursday night as they chanted for their cause in the upper stands, with one of them supergluing his bare feet to the stadium’s floor.

The incident unfolded around 8 p.m., just as players Coco Gauff and Karolina Muchova were starting the second set of their semifinal.

Videos shared on social media show two men and a woman standing up and shouting from their seats in the upper stands, wearing shirts that say “End Fossil Fuels.” They’re met with a chorus of boos from surrounding spectators as a security guard threatens to kick them out.

Police eventually responded and escorted the protesters away, though responders had to step in to safely unstick activist Shayok Mukhopadhyay from his spot, according to the NYPD. It’s unclear how exactly they did that.

Police said they arrested Mukhopadhyay, 50, of White Plains, New York for trespassing and disorderly conduct. They also arrested 35-year-old Gregory Schwedock, of Manhattan, for trespassing. Both were given desk appearance tickets.

“We achieved a significant disruption in business as usual,” Mukhopadhyay told Gothamist by phone on Friday. “And people have to understand, like, you know, the disruption that I did is nothing compared to the disruption caused by the climate crisis.”

Mukhopadhyay and his fellow protesters represent the group Extinction Rebellion NYC. They claimed they weren't protesting tennis's role in fossil fuel emissions, but rather the government’s weak response to the climate crisis.

Mukhopadhyay said he works as an artist and documentary filmmaker. He was spurred into climate activism three years ago after visiting his family in the Bengal region of India, where he said people who have little impact on climate change are unfairly bearing the brunt of pollution from wealthier countries.

In choosing to protest at the U.S. Open semifinals, he said his group was looking for a way to catch as much attention as possible. The annual Queens tournament is one of the premier events in professional tennis and draws a global audience.

When the fracas and resulting police response caused the match to be delayed by almost an hour, fans weren’t happy – and Mukhopadhyay said he wasn’t surprised.

“I think tennis fans, especially in the section where I was sitting, come from a very privileged section of society. And so they are fairly insulated from climate disasters,” he said. “I didn't expect them to be pleased. I mean, they would not be pleased if there was a two-hour rain delay. Right?”

The group said its aims include wanting the Biden administration to “tell the truth by declaring a climate and ecological emergency,” halting biodiversity loss, and reducing greenhouse gas emissions to net zero by 2025.

As temperatures this week soared through the 90s, players sometimes struggled to push through the heat.

Russian player Daniil Medvedev, who won the tournament in 2021, warned during a match against Andrey Rublev on Wednesday that “one player [is] gonna die, and they’re gonna see.” According to the Associated Press, Medvedev had to use an inhaler at one point, and a doctor had to check his breathing with a stethoscope.

“Tennis-as-usual won't be possible on a planet in which humanity fails to keep global warming below 1.5 degrees Celsius. If activists don’t disrupt these games, the climate will,” said Extinction Rebellion spokesperson Mun Chong in a written statement.

Triple-digit temperatures and monsoonlike rain delayed play at the Australian Open in January.

In a statement on X, the U.S. Tennis Association said three of four protesters involved in the disturbance “were escorted out of the stadium without further incident.”

“The fourth protester affixed their bare feet to the floor of the seating bowl. Due to the nature of this action, NYPD and medical personnel were needed in order to safely remove this individual from the stadium,” the statement read. “The four protesters were taken into NYPD custody. In total, 49 minutes elapsed before play resumed.”

Mukhopadhyay declined to go into detail about what exactly he used to glue his feet to the floor, saying he wanted to “focus on the big picture.” He said first responders used some sort of solvent to unstick him.

He said he wasn't physically injured by the stunt, but added that he was disturbed when the NYPD forced him into a psychiatric evaluation.

“I thought this only happened in the former Soviet Union, to try to paint people who politically disagree with the government as crazy people,” he said.

Despite the interruption, Gauff swept the match, winning two straight sets to advance to the finals this weekend.

This story has been updated with additional comment.