One source said police received a report that the fire started from a liquid that came out of a paper bag held by a man who appeared to be in his 60s.
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Tokyo is reportedly looking to send lower-level officials to the Winter Olympics, a far cry from when then-Prime Minister Shinzo Abe traveled to the Pyeongchang Games in 2018.
The comment and apology were widely condemned on social media, with many criticizing the announcer, Hall of Fame pitcher Jack Morris, for saying he was sorry if he offended anyone.
The men's marathon and the biggest game in Japanese basketball history should be the highlights of Tokyo 2020's final day.
Samurai Japan will look to give the baseball-mad country its first Olympic gold in the sport, while one of Japan's flagbearers finally gets her chance to leave another mark on the Games.
On Friday, Japan's women's basketball team looks to book a spot in the gold medal game while action at National Stadium continues with the men's and women's 4x100-meter relays.
The first medals for sport climbing are ready to be handed out while karate makes its long-awaited Olympic debut as Tokyo 2020 moves into the final homestretch.
An East Asian rivalry is set to be renewed on the diamond and skateboarding returns to the schedule a little over a week after Japan claimed the sport's first two gold medals.
A gymnastics legend is set to make her return while Japan looks to the boxing ring to bust its gold slump as the Tokyo Games move into the final handful of days of competition.
A weightlifter from New Zealand will make Olympic history while Samurai Japan takes on the United States in a battle of gold medal contenders on Day 10.