Few people noted last December's arrest of Gunner Joseph Fisher for threatening to commit mass violence. But Antioch High School shooter Solomon Henderson took notice, including it in his diary.

Federal agents arrested a teenager over a plot to carry out a mass shooting at a Nashville mosque, News Channel 5 reported on Monday. The plot had first been flagged in December by Court Watch, according to reporter Phil Williams,

An FBI investigation has revealed a Middle Tennessee teen's plan to carry out a mass shooting last year. According to recently released documents, the FBI investigation began by looking into the owner of an Instagram account that was posting or sending messages to another user explaining he or she was planning to conduct a mass shooting.