Thousands of visitors flock to National Harbor each day, transforming the development into one of the most bustling areas across Greater Washington — but all of that foot traffic has also allegedly attracted the worst kind of attention.

Federal prosecutors revealed earlier this week that they’d arrested a Maryland man who they believe was planning to plow a rented van into crowds at National Harbor. Officials said the man was inspired by similar terror attacks across the country, and chose the Prince George’s County development after initially spending time scouting Washington Dulles International Airport.

The incident has proven to be a chilling reminder for executives with Peterson, National Harbor’s master developer, of the value of preparing for every possible scenario.

Read more: Washington Business Journal