October 17, 2013
UPDATE: The plaza as well as the streets have been reopened after police said the “suspicious device” had “no merit.”
Police closed off the area surrounding and including Union Square, a public plaza near downtown San Francisco, Calif., after discovering a “suspicious device” near the intersection of Market and Fourth Street on Thursday.
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People in businesses around the area, including a Macy’s and Saks Fifth Avenue, were told to “shelter-in-place” as police set up a perimeter with barricades.
Suspicious device Market St and Powell St, O'ffarell St. Street Closure, heavy traffic, Cable Car and Muni rerouted and delayed. AVOID AREA.
— San Francisco Police (@SFPD) October 17, 2013 
The square was under preparations for the Nike Woman’s Marathon this weekend.
Market and Fourth Street is a busy intersection with major retail stores nearby, including an Apple Store, a Ferrari Store, a Ross clothing store, and an Old Navy Flagship store.
Union Square refers to a 2.6 acre public plaza bordered by Geary, Powell, Post and Stockton Streets as well as the retail outlets, hotels, and theaters in the vicinity.
The district’s name dates back to the American Civil War where the area was used for rallies in support on the Union.
Union Square is now listed as a California Historical Landmark.