A bus tour of commercial real estate in Northern Virginia alarmed Arlington residents and workers who didn’t know what to make of the large police escort winding its way through local neighborhoods.

The annual tour is organized by NAIOP, a commercial real estate development association. This year the NAIOP Northern Virginia Bus Tour made stops in Arlington, Alexandria, and parts of Fairfax County including Tysons Corner.

“Considered to be one of the premier commercial real estate Bus Tours in the United States, NAIOP Northern Virginia’s 2013 Tour… is a full day of information and news about our market,” said NAIOP’s website.

The tour involves multiple buses full of real estate professionals and local officials, and a sizable police motorcycle escort. Since it’s not very well publicized outside of the real estate community, locals didn’t seem to know what to make of it when it rolled by in Ballston, Clarendon, Rosslyn, Crystal City and elsewhere.

“Something weird is going on in Rosslyn,” said one reader, in a voicemail left for ARLnow.com. “There are cops everywhere.”

“A dozen or so ACPD motocycles, with sirens blaring, just escorted a number of buses, maybe 4 or 5, through Ballston,” said an email. “Any idea who was in the buses?”

“11 tour buses led by 30 cops on motorcycles riding through Clarendon… um what?” said a reader via Twitter.

“@ArlingtonVA PD has practically shut down Crystal Dr for the NAACP (sic) 2013 Bus Tour,” said another tweet.

The tour was scheduled to start at 7:30 a.m. and end at 3:00 p.m.

Photos via @RosslynVA and @josephgruber