The Apollo Theatre in London partially collapsed Thursday while about 700 people were inside during a performance. More than 40 were injured, The Associated Press reported.
Police said they weren't aware of any fatalities "at this early stage," and that five seriously injured people had been taken to hospitals following the incident at the Apollo Theatre on Shaftsbury Avenue at 8:15 p.m. local time. More than 40 "walking wounded" are being treated at a nearby theater, police added.
Urgent: Do You Approve Or Disapprove of President Obama's Job Performance? Vote Now in Urgent Poll
Martin Bostock was in the audience with his family, and said "complete chaos" erupted in the theater.
"At first we thought it was part of the show," he told Sky News. "Then I got hit on the head."
London was hit by a freak thunderstorm about 7 p.m. that dumped heavy rain on the city, but it wasn't immediately clear if that was related to the collapse.
The fire department said all casualties who were trapped in the Apollo Theatre had been freed. It wasn't immediately clear if the roof, ceiling or balcony collapsed at the theater during a performance of "The Curious Incident Of The Dog In The Nighttime." Special search and rescue teams remain on the scene, along with ambulances and police.
Witnesses told British media that the theater in London's famous West End was packed during the holiday season to see the show, which is based on the best-selling novel by Mark Haddon.
"We thought it was part of the show, until something hit me on the head very hard," one man told the BBC, speaking from the foyer of the theater while he was being evaluated by emergency workers. "I thought we were all going to be in really, really serious trouble."
"Within an instant, the entire roof caved in," another witness told the BBC.
London's fire department said eight engines are on the scene in the SoHo neighborhood, and the city's ambulance service said it had sent "a number" of crews to the theater.
The Apollo Theatre, named for the Greek and Roman god Apollo, god of music and the arts, was built in 1901 and has 775 seats.
On its website, the theatre warned that its balcony was one of the steepest in London "so avoid if you have trouble with heights."
Editor's Note: ObamaCare Is Here. Are You Prepared?
© 2015 Newsmax. All rights reserved.