The mayor of Houston imposed a curfew in his city on Tuesday, ordering nearly everyone off the streets from midnight to 5 a.m. in an effort to stop “small-scale looting” and other crimes following prodigious flooding from Tropical Storm Harvey. Houston has a population of 2.3 million people spread across nearly 670 square miles, making the curfew among the largest and most expansive in United States history.

In times of natural disasters or violent unrest, American cities have imposed curfews to try to bring order during chaos. The following curfews were some of the largest or most significant in the country’s history.

1992: Riots in Los Angeles

The acquittal of four Los Angeles police officers on April 29, 1992, in the vicious beating of Rodney G. King, a black motorist, prompted widespread looting, relentless violence and arson in the city. Hundreds of fires burned throughout the city; firefighters racing to extinguish them were shot at; and looters snatched merchandise from stores.

Seeing no signs of conditions improving, Mayor Tom Bradley imposed a dusk-to-dawn curfew in the worst parts of the city on April 30, but soon expanded it to all of Los Angeles, which then had a population of more than 3.4 million.