Six Irish nationals have been killed after a balcony collapsed in Berkerly, California.br br They were attending a birthday party in the area popular with students when the tragedy happened.br br JUST IN: Coroner confirms sixth fatality in #Berkeley apartment balcony collapse pic.twitter.comVFIb8VZtgI— KPIX 5 (@CBSSF) June 16, 2015br br br A number of others have been seriously injured in the accident.br br Police are investigating the cause of the collapse.