UPDATE: From the comments, here are first-hand accounts of what happened from students who were present:
There were several of us [students] there until about 10:30 when Professor Safranek was ready to retire for the evening (I believe he arrived around 9:00 p.m.). There were two gentlemen escorting him and standing at his office, never leaving his side. I have no idea where they came from, but I have never seen them at Ave. Though, they treated Professor Safranek respectfully, given the situation.and
A few students were there to show our support and assist in the loading of the materials. Several other students had also waited at least an hour, but were unable to wait for the unloading. . . . . I've worked with plenty of security personnel, and if I had to rely on those experiences alone, I'd say [the two gentlemen] were security. Friendly, but not too friendly. Quiet, but watchful. Relaxed, but under orders.
The two fellows with Safranek were Domino security. (They removed their jackets b/c the temperature on the building was a bit warm.) I recognize one of them as occasionally filling in here at AMSL on the weekends. The other I had never seen before that evening.
They were very pleasant and low-key and even helped Safranek load his stuff and carry it out to his vehicle. They were very respectful of the professor and of the students who stopped in to say hello.

