Police said officers were called at around 2015 GMT (3:15 p.m. EST) to reports of a ceiling collapse at the Apollo Theatre on Shaftsbury Avenue in central London.
It said police "are aware of a number of casualties" but had no further details.
London's fire department said eight engines are on the scene in the SoHo neighborhood.
The Apollo Theatre is currently showing "The Curious Incident Of The Dog In The Nighttime."
Copyright (2013)