The shooter was at a dinner prior to Friday's rampage at which mass-shooting videos were viewed, an official said.
A married couple's bodies were found in snow along a road in rural Arizona where a major wintry storm hit a week ago.
"We can't help but be extremely disappointed that, despite all its efforts, the United States government was unable to secure his release," the family said.
The girl was visiting her father when she was led to believe that if she didn't remove her clothes she wouldn't be able to see him, according to reports.
Police said Marcquis Graham, of Philadelphia, and four others staged a "violent altercation" and yelled about guns for a video that was going to be posted on social media.