As a giant excavator swallowed its way closer, hundreds of police, unfazed by the pyrotechnics propelled at them, dragged protesters from their stations.
A law enforcement official said the devices were made with a 1-inch-by-6-inch length of PVC pipe filled with suspected pyrotechnic powder and broken glass to serve as shrapnel.
The two owners, and two members of the band whose pyrotechnics started the blaze, have been arrested (one of the owners is in hospital after trying to commit suicide).