Lockdown at American University in Washington, DC called off despite failure to locate armed person near campus

Washington DC's American University (AU) was under lockdown for several hours on Wednesday after an armed attacker was spotted in the neighbourhood, sparking panic on campus.The lockdown prompted university and city police to search the campus, although there were no immediate reports of shots fired or people injured.The Washington Post reported that an armed man was seen at Block-3300 of New Mexico Avenue NW on Wednesday. Most of the students and teachers were reported to be away from the campus, but a few of them were still inside offices and classrooms.The AU police department immediately issued an alert and advised the varsity to shut down temporarily.The university notified the public about its lockdown through social media and warned people from the locality to stay indoors.The varsity also sent text messages and e-mails to students and teachers to warn them about the situation. After the lockdown was issued, the university tweeted out updates on the situation constantly. However, a few hours later, after the AU police department had conducted its searches and gave a notice saying that the varsity grounds and locality were clear, AU tweeted saying that the lockdown was lifted and that the grounds were secure. This incident came four months after a deadly shooting at the University of Florida claimed 17 lives in February. The US has experienced a string of mass shooting incidents over the past few years.With inputs from Reuters