Police said in a probable-cause statement released Friday that officers took Sterling into custody at the Phoenix Convention Center after someone contacted Hawthorne, California, police to report that he was posting threats on Facebook about killing officers at the Comicon event. The local man was wearing all black, however, it is unclear if he was in costume or not.
The ban on props originally pertained just to weapons, but was later expanded to include all props.
Police say Sterling also planned to kill a performer at the event, actor Jason David Frank, pictured.
"That person knew that those posts could be credible and immediately alerted law enforcement and prevented a tragedy".
Police say Sterling was armed with a shotgun and three handguns that were all fully loaded.More news: James passes Jordan, Cavs back in Finals with 135-102 win
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"In this day and age, with everything that's occurring, I think that we just have to be mindful on the safety of everyone that's attending this event", said Fortune. Security staff at the Phoenix Comicon are supposed to inspect prop weapons, as a matter of course, but in this case, Phoenix police said that did not happen. The Phoenix Comicon is being held at the Phoenix Convention Center in the downtown area of Arizona's capital.
The man was allegedly armed, and had to be subdued by multiple officers. Purchased props will be wrapped by the vendors and must remain so while they are on-site. This has resulted in enormous lines and extended waiting times to get into the event.
Along with the weapon ban, added screening measures have been put in place since the incident, so ABC 15 advises attendees to be prepared for the wait. According to NBC affiliate, KPNX 12 News TV, this weekend, there will be an increased number of both uniformed and plainclothes officers at the event.
This Thursday, May 25, 2017, photo provided by the Maricopa County Sheriff's Office shows Matthew Sterling in Phoenix, Ariz. You can view the complete ticket pricing information here.