PARIS (AP) — French authorities say four people have been killed and 14 injured when a third-floor balcony collapsed in the western city of Angers.

The Angers prefecture says the accident happened Saturday night during a party at an apartment in a recently constructed building. They say one of the injured is in serious condition.

Michel Pichon, the director on duty at the Angers teaching hospital, told the Franceinfo radio-television station that the injured were all about 20 years old.

An investigation has been opened to establish the cause of the accident.