As police tried to control the crowd, fireworks exploded on the street, sending people running for cover.
The gathering happened after a Tik Tok video promoting a birthday party went viral.
Police had monitored social media posts and were prepared for an unruly crowd.
They declared an unlawful assembly – then later ordered the area evacuated due to a bomb threat.
But that didn’t send the crowd home – with many continuing to jam the streets.
At least one police cruiser also had a window shattered, possibly from the fireworks.
Police say they found no explosive device following the bomb threat.
An emergency curfew was imposed for the downtown area from 11:30 p.m. to 5:30 a.m.
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