▁Park ▁neighborhood ▁of ▁the ▁city ' s ▁North ▁Side . ▁The ▁second ▁and ▁third ▁flo ors ▁were ▁being ▁used ▁as ▁a ▁party ▁ven ue ▁at ▁the ▁time ▁of ▁the ▁collapse . ▁Most ▁of ▁the ▁party - go ers ▁were ▁in ▁their ▁early ▁ 2 0 s , ▁and ▁knew ▁each ▁other ▁from ▁their ▁days ▁at ▁New ▁T rier ▁High ▁School ▁and ▁Lake ▁Forest ▁High ▁School ▁of ▁Chicago ' s ▁North ▁Sh ore ▁sub ur bs . ▁One ▁witness ▁says ▁she ▁war ned ▁other ▁people ▁in ▁the ▁building ▁that ▁the ▁bal con ies ▁were ▁unsafe , ▁but ▁another ▁later ▁said ▁that ▁" it ▁looked ▁like ▁it ▁was ▁newly ▁built . ▁It ▁looked ▁st ur dy ." ▁ ▁Col lapse ▁About ▁fifty ▁people ▁were ▁on ▁the ▁top ▁wooden ▁bal con y ▁at ▁the ▁time ▁of ▁the ▁collapse . ▁According ▁to ▁one ▁witness , ▁the ▁sound ▁of ▁spl inter ing ▁wood ▁was ▁heard ▁immediately ▁before ▁the ▁collapse , ▁which ▁occurred ▁shortly ▁after ▁mid night ▁local ▁time . ▁The ▁collapse ▁started ▁on ▁the ▁third ▁floor , ▁pulling ▁down ▁other ▁bal con ies ▁below . ▁The ▁first , ▁second , ▁and ▁third ▁floor ▁bal con ies ▁all ▁col lapsed ▁into ▁the ▁bas ement ▁below , ▁carrying ▁a ▁total ▁of ▁approximately ▁one ▁hundred ▁people ▁among ▁them . ▁Several ▁people ▁were ▁also ▁tra pped ▁in ▁a ▁bas ement ▁st air well . ▁Sur viv ors ▁helped ▁to ▁pull ▁vict ims ▁out ▁from ▁under ▁the ▁de br is ▁of ▁the ▁bal con ies , ▁and ▁rescue ▁workers ▁had ▁to ▁use ▁ch