A woman was arrested outside the White House with a gun moments after President Obama concluded his speech on immigration Thursday night, a Secret Service official told Fox News. The woman was carrying a 9mm handgun in a holster that was observed by two plain-clothes agents, who notified Uniformed Division officers who arrested the woman for carying an unregistered firearm. April Lengart, a 23-year-old Michigan native, was not cooperating in an interview, the official said. She was with another individual, who was not arrested. Earlier this week the Secret Service arrested an Iowa man who was found to have a .30-30 rifle, 40 rounds of ammunition, and a six-inch knife in his car parked near 1600 Pennsylvania Ave.