LONDON — A protester set fire to his arm after running onto the court during a match on Friday at the Laver Cup tennis competition, stunning the capacity crowd at London’s O2 Arena and briefly setting fire to the playing surface.

Wearing a white T-shirt reading “End UK Private Jets,” the protester, a young man, appeared on the court during the afternoon singles match between Stefanos Tsitsipas and Diego Schwartzman. Sitting down near the net on Schwartzman’s side of the court, the man briefly set fire to his right arm, and to the court, as security officials ran toward him.

The protester appeared to immediately regret the decision to set fire to himself, and quickly put out the flames with his left hand while a small fire burned on the court next to him. A staff member smothered the on-court fire with a suit jacket while the protester calmly waited to be removed.

Once the fire was out, and with Schwartzman keeping a safe distance, three security guards carried the man off the court to a chorus of boos from the crowd.

“He came out of nowhere,” Tsitsipas said. “I have no idea what this was about. I’ve never had this happen in a match before. I hope he’s all right.”

The man did not seem to be seriously injured.

Disrupting high-profile sporting events has become an increasingly common tactic by environmental activists in Europe over the past year, and some have succeeded in drawing attention to their causes in a variety of ways, including attaching themselves to goal posts at Premier League soccer matches; breaching the court at the French Open tennis championships; and blocking the path of cycling’s Tour de France.

The incident at the Laver Cup appeared to leave the court undamaged, and play resumed after a brief delay. Tsitsipas went on to defeat Schwartzman in straight sets.