New research points to a phenomenon quickly remaking the face of homelessness in the United States - the rise of the "tent city".
These permanent and semi-permanent encampments are set up by homeless people, mostly without the authorities' permission.
Tent cities exist in every state of the country and the District of Columbia, and have grown by 1,300 percent over the past decade, according to findings released by the National Law Center on Homelessness & Poverty.
Nearly a fifth of the encampments studied included more than 100 residents. Just 4 percent of these tent cities were found to be legal. Nearly two-thirds of those included in the study had been in existence for more than a year, and more than a quarter had been in place for more than five years.