Several other tennis players, like Rafael Nadal, Serena Williams, Naomi Osaka, and Kei Nishikori are also unsure of their participation.
The government is likely to extend Tokyo's emergency and put the same order on northern Hokkaido, which is set to host the marathon.
Saina Nehwal and Kidambi Srikanth were looking forward to the Singapore Open, seen as their last chance to book their spot in the Tokyo Olympics.
Horton had refused to stand on the podium with Yang at the world championship in 2018 and had also branded him a "drug cheat" at Rio.
The governor of Kanagawa in a press conference said they cannot prepare beds for Olympic athletes.
The protestor was shut down by Mark Adams, the IOC’s Presidential spokesperson, and the video of the incident was later deleted.
The government plans to cover each towns’ expenses for COVID-19 countermeasures and has prepared the necessary guidelines.
Sabre fencer C. A. Bhavani Devi created history by becoming the first Indian fencer to qualify for the Olympics.
Saina Nehwal and Kidambi Srikanth are unlikely to make it to the Tokyo Olympics due to the cancellation of the Singapore Open.
Chopra has not featured in any international competition since securing his place in the Olympics, in South Africa in 2020.