Trump walking back to the White House after standing for photos outside St John's Episcopal church across from Lafayette Square on June 1. Photo: Brendan Smialowski/AFP via Getty Images

Federal officials stockpiled ammunition at the D.C Armory and sought crowd control devices before law enforcement forcibly cleared protesters from Lafayette Square in June, a whistleblower told Congress, per his written submissions to Congress.

Why it matters: D.C. National Guard Maj. Adam DeMarco's testimony is a part of a congressional investigation into law enforcement's use of force against demonstrators protesting George Floyd's death in the square.