More than 20 people have developed sore throats near a luxury department store in Tokyo's ritzy Ginza shopping area after a person allegedly sprayed an unknown substance.
The Tokyo Fire Department said 26 people complained of suddenly developing throat pain and felt unwell near the Ginza Six shopping complex, and all but one of them were taken to a hospital.
Their symptoms were believed to be mild, officials said.
Fire department and police officials said an investigation was under way. The largest-circulation Yomiuri newspaper said police have detected traces of pepper spray on the wall.
Dozens of fire engines and ambulances were parked outside the complex, and the surrounding roads were temporarily closed.
Television footage showed firefighters and officials in hazmat suits assisting people, with some being brought out of the building.
Yuzo Tsuda, a 78-year-old Tokyo resident, told The Associated Press he walked toward the shopping complex after having lunch with friends, drawn by the commotion, when he suddenly felt pain in his throat and started coughing.
He said the ache in his throat subsided about an hour later and he did not plan to go to the hospital.
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