PHOENIX — In June 2015, legal and civil rights groups filed a class-action lawsuit in Federal District Court in Tucson accusing the Border Patrol of holding migrants in dirty and crowded cells at stations in southeastern Arizona, after they were caught illegally entering the United States.

Late Wednesday, still images from surveillance video at the stations, offering a glimpse inside the cells, were publicly released. The videos were part of the evidence filed with the court during the discovery process and unsealed by Judge David C. Bury last week.

The lawsuit was filed on behalf of migrants by the American Civil Liberties Union of Arizona, the American Immigration Council, the National Immigration Law Center and the Lawyers’ Committee for Civil Rights of the San Francisco Bay Area..