A fourth-floor balcony gave way during a party in northern California late last night, killing at least six exchange students in a building close to the University of California, Berkeley. Seven other people were injured, some of them seriously.

"All of those killed and most of those injured are Irish nationals, exchange students visiting the Bay Area to work for the summer," reports Dan Brekke of member station KQED. He adds, "Berkeley police say the collapse occurred at 12:41 a.m. [local time] during what's reported to have been a 21st birthday party for one of the students."

Update at 2:15 p.m. ET: Possible Causes

While some reports have suggested too many people at the apartment might have crowded onto the small balcony, KQED cites local media saying that photos from the scene suggest a lack of adequate waterproofing where wooden support beams meet the building's facade.

Our original post continues:

Ireland's minister for foreign affairs, Charlie Flanagan, issued a statement:

"It is with great sadness that I confirm that a number of young Irish citizens have lost their lives while a number of others have been seriously injured following the collapse of a balcony in Berkeley, California earlier today."

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