Several rallygoers reported to local officers that Crooks was acting suspiciously and pacing near the magnetometers, according to a law enforcement official who spoke on the condition of anonymity because the official was not authorized to discuss the investigation.
The suspicious person, later identified as Thomas Crooks, 20, was first flagged to local police officers by rallygoers on their way into the event. The attendees reported they saw Crooks pacing and behaving strangely near the magnetometers, four officials told NBC News.
ABC
https://abcnews.go.com/US/wireStory/signs-trouble-trump-rally-evident-minutes-gunman-opened-111966629
NBC
Local Channel 7 https://x.com/WJHG_TV/status/1812977981989535933