When an FBI agent was exposed for masquerading as an Associated Press journalist in 2014, the media condemned the tactic, saying sources would be afraid to speak freely to reporters.
The FBI is boosting its investigation of Russian hackers who are believed to be targeting the Democratic Party and politicians.
A man arrested twice on suspicions of robbing banks has sued the FBI, the city of Denver and its police department, claiming he was falsely arrested and subjected to excessive force and malicious prosecution.
An undercover ATF vehicle was broken into and valuable equipment stolen in Detroit on Thursday.
