A flash mob involving an estimated 200 young people turned violent at the Mall of America in Bloomington, Minn., on Monday—turning one of the busiest shopping days of the year at the nation’s largest mall into chaos. At least 10 juveniles have been arrested in the incident on suspicion of disorderly conduct, but there were no weapons involved and no theft has been reported. A mall spokeswoman said the riot started around 4:20 p.m. with a single incident in the food court and then quickly spread and officials put the mall on lockdown, although they later called that a premature move. More than 30 Bloomington police, as well as Metro Transit and Richfield officers, responded to the call, and order was restored by 5:30 p.m. Mall officials said they will review security measures to determine how the situation descended so quickly into chaos.