ARLnow.com reports that a white BMW exploded in the Penrose neighborhood of Arlington around 8:15 a.m. this morning. The vehicle was parked around several homes, but as ARLnow points out, there are a pair of large apartment high-rises and the headquarters for the Department of Defense’s Defense Information Systems Agency is only a couple of blocks away from the explosion site. Police reportedly have a “person of interest” in custody; a search for additional explosives in the area found none.