Large groups of unruly teenagers at an Illinois pool and California mall prompted early closures that resulted in arrests, highlighting what experts call a symptom of cultural breakdown.

Thousands of people are expected in Belfast for the week-long celebration of Irish traditional music.

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External theft — which includes things like "flash mob" thefts, shoplifting and organized retail crime — accounted for 36% of losses.

The team presented a sensational flash mob at New York’s Times Square. The 13-city tour kicked off in Atlanta recently.

Since then, other flash mobs have turned up in Los Angeles, Orange and Riverside counties, mainly targeting high-end chain stores in malls.

It's another ‘‘flash mob'' strike, wherein a crowd, organized by e-mail lists and Web sites, converges in prearranged location and performs a wacky, harmless stunt for a few minutes in public.

Thousands of people are expected in Belfast for the week-long celebration of Irish traditional music.