Updated 8/4/12 at 6:15 p.m.

CHICAGO (CBS/STMW) – Lollapalooza will close a half hour later than usual at 10:30 p.m. due to severe thunderstorms that passed through the Chicago area, which caused concert promoters to suspend the event.

Festival-goers were evacuated from Grand Park were directed by staff and the Chicago Police Department to pre-established underground evacuations and shelters along Michigan Avenue, according to a press release.

The three emergency evacuation shelters were the Grant Park North, Grant Park South and East Monroe Street Garages. All can be entered through vehicle entrances on Michigan Avenue.

Some concert-goers told CBS 2’s Suzanne Le Mignot that they did not hear mention of temporary shelters in the PA announcements. They were headed to their friends’ places or hotel rooms.

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