Officials investigating the collapse of a ceiling at a London theatre which injured nearly 80 audience members have concluded the disaster was caused by deteriorating building materials which had been in place for more than a century.

The incident occurred at the Apollo Theatre in December (13) during a performance of The Curious Incident of the Dog in the Night-Time and prompted owners to close the venue and move the show while repairs were carried out.

Local officials launched an investigation and a representative for Westminster council has now confirmed the disaster was caused by the deterioration of cloth and plaster ties which were holding up the timber ceiling frames, which had been in place since 1901.

The spokeswoman tells Britain's The Guardian newspaper, "Our investigation is still ongoing. However, our inquiry to date has led us to understand why the ceiling at the Apollo theatre failed in December. The principal cause was the deterioration over time of wadding ties which supported the ceiling, thought to be in place since its construction in 1901."

The council will now issue a warning to owners of other historic theatres across the British capital to insist on regular maintenance.

The Apollo is due to reopen this week (beg24Mar14) with a production of Let The Right One In.