Reports of a gunman on campus led to the lockdown of American University in Washington, D.C. on Wednesday night turned out to be an off-duty police officer, according to Assistant Police Chief Diane Groomes. Officers were alerted about a suspected man with a gun before 8 p.m., and the school's Twitter account advised students to "shelter in place," and released a photo of two suspects with a warning not to approach them. The lockdown was lifted before 9:30, and the suspect was reported to be an off-duty officer with a concealed weapon.
