Metropolitan Division officers finish another "rollback" operation. They searched the apartment of a paroled armed robber and gang member. These rollbacks are a cornerstone of the Metro Division's strategy of tracking people who may re-offend, and suppressing crime before it happens. Martin Kaste/NPR hide caption

itoggle caption Martin Kaste/NPR

Democratic presidential candidate Hillary Clinton responds to the cheers of supporters at a Jefferson Jackson event hosted by the Democratic Party of Virginia at George Mason University's Patriot Center in Fairfax, Va., last Friday. Manuel Balce Ceneta/AP hide caption

itoggle caption Manuel Balce Ceneta/AP

NOAA scientists estimate they saw about 10 billion sea scallops off Delaware and southern New Jersey this spring as part of an annual survey. Andrew Martinez/Science Source hide caption

itoggle caption Andrew Martinez/Science Source