Still more bad news to report at Westfield Montgomery Mall this week: The two-year-old Core clothing store has closed its doors, and bankrupt-again Radio Shack will soon be out as well. The mall has seen more departures these past few months than at any time in recent memory, from national retailers that went bankrupt (The Limited, American Apparel and Marbles) to smaller tenants like Best Buy Mobile, R. Riveter, American Classic Clothes, Freddy, Smart Toys and Stride Rite. Losses have been heavy on the dining side as well: Splashy new restaurants MET Bethesda and Naples Ristorante each flamed out after less than two years, as did the short-lived Peet’s Coffee bar as well as longtime tenants Wetzel’s Pretzels and Bistro Sensations. Similar scenes are playing out at malls across the country, as internet sales continue to cannibalize physical stores. Just this week, Urban Outfitters CEO Richard Hayne told Bloomberg that the U.S. is oversaturated with retail space after a late-’90s/early-2000s building boom. “Like housing,” he said, “that bubble has now burst.”