At least 11 people were killed in the US city of Chicago when a third-floor balcony collapsed during a party in an apartment building. The balcony crashed all the way to the ground, crushing the second floor balcony beneath it and trapping some people in the basement level. Between 40 and 50 people were reportedly on the balcony at the time of the collapse, which happened at around midnight local time in the Wrigleyville area of the city's North Side. Of the 35 people who were injured, 11 were said to be in a serious condition.