The mall is very close to the Mosque at 1600 PA Avenue. Infidels should stay clear of the Mosque. You may be able to catch a glimpse of the Imam Soebarkah on Sunday. If you see him, you may wish him a Blessed Ramadan.
From my firsthand experience, DC after dark is a gamble if you are white. I myself would vacate before dark. I made the mistake of being there on the streets after sundown once, and I wont do it again.
You mean the White Mosque where Imam Obama lives?