All visitors were forced to evacuate the All England Club after a fire alarm went off at the end of play on day three of Wimbledon.
Centre Court, which staged second-round matches for Novak Djokovic, Marin Cilic, Serena Williams and Kei Nishikori, was the first to be evacuated.
Every court in the ground was eventually cleared and fire engines arrived at the scene, but they did not find obvious signs of a blaze.
"The cause of the evacuation was not immediately clear, amid suggestions it may have been caused by an electrical fault," BBC News quotes a Wimbledon spokesperson as saying.
Fire alarms went off earlier in the day on Court One, but officials have confirmed that it was a drill.
