Nasire Best, 21, fired shots toward a White House security checkpoint Saturday evening and Secret Service officers returned fire, according to the District of Columbia Metropolitan Police Department. A bystander was struck by gunfire.

Correspondents stationed near the White House said they heard what appeared to be repeated gunfire on Saturday, triggering an immediate security response around the grounds.

CNN reporters heard what appeared to be dozens of gunshots near the White House, triggering a lockdown and a rapid response from the US Secret Service.