About 1,600 people evacuated the Shinbashi Enbujo theater in Tokyo's Ginza district after a small fire broke out Wednesday evening in the subbasement, police said.
No one was seriously hurt, although several employees complained of sore throats, the Tokyo Fire Department said.
The fire department said the blaze broke out below the stage roughly 30 minutes after a musical starring pop idol Hideaki Takizawa began at 6 p.m. The fire caused damage to sets and props before being put out just after 7 p.m.
The traditional theater was packed with about 1,400 guests, mostly women, according to Shochiku Co., which runs the premises.
The Metropolitan Police Department said it suspected that a prop spewing fire that was to come up through the stage during the performance might have been dropped.