The new commissioner for the United States Border Patrol's parent agency released a critical report on Friday amid complaints that agents used excessive force, according to The Associated Press.
The 21-page report, which does not address specific cases, said some agents may fire at rock throwers and vehicles because they are frustrated, the AP reported.
The Police Executive Research Forum found some agents are suspected of intentionally placing themselves in the escape route of assailants in fleeing vehicles before firing guns, creating justification to use deadly force, the AP reported.
The report said some shootings of rock throwers were questionable, especially when the attackers were hurling projectiles from across the border in Mexico, according to the AP.
The report was released with revised guidelines on use of force that prohibits agents from firing at moving vehicles or rock throwers unless there is "imminent danger of serious physical injury or death" to them or someone else, the AP reported.
The Customs and Border Protection agency had kept the report under wraps since it was completed in February 2013, resisting calls from members of Congress and immigration activists, according to the AP.
R. Gil Kerlikowske was noncommittal at his confirmation hearing in January but said Friday that he prevailed in an internal debate about whether the report should be made public, the AP reported.
The agency had refused to make the report public even after the Los Angeles Times reported on its contents in February, according to the AP. The American Civil Liberties Union's San Diego affiliate sued in federal court last week to try to force the agency to turn it over.
Immigration activists who urged Kerlikowske to release the report when they met with him Tuesday in San Francisco, claimed victory, the AP reported.
