Dozens of protesters in New Orleans tried to force their way past police into an already-crowded city council meeting on demolishing public housing units.
The US federal housing authority will knock down 4,500 housing units damaged by Hurricane Katrina so developers can build mixed-income housing.
Critics of the plan say it will further reduce the city's stock of cheap housing, already badly shrunk by Katrina.
Police used stun guns and pepper spray to keep the protesters from breaking through an iron gate into the city hall.
Several people were treated for the effects of pepper spray.
Tensions have been high in New Orleans over the city's dire housing situation. Several people were ejected from the council chamber as the meeting began.