He checked in as a visitor – and was closely armed: When the president got here to dinner, the suspected murderer was already within the resort. The man himself was apparently shocked on the lax controls.
https://www.spiegel.de/ausland/attentatsversuch-in-washington-eine-treppe-trennte-ihn-vom-ballsaal-a-9894bc39-7674-4eb1-a8df-1cbf059d8e52#ref=rss