The former U.S. Capitol Police chief said the principal security officials for the House and Senate resisted calling in help from the National Guard before the Jan. 6 protests that turned into a mob assault on the building. Steven Sund, who resigned from his role as Capitol Police chief after the attack, plans to tell two Senate committees that the House and Senate sergeants-at-arms, who are also testifying in the same Senate hearing, didn’t adequately prepare for the planned rally by Donald Trump’s supporters. Sund also blames the other authorities for delaying a request for backup from the National Guard once the attack was underway. The joint hearing of the Senate Homeland Security and Rules and Administration Committees on Tuesday is the first in a series of lawmaker inquiries into the origins of the Jan. 6 insurrection and the failure of the Capitol’s security forces to anticipate and then quell the riot, which left five people dead. Sund will testify along with former Senate Sergeant-At-Arms Michael Stenger and former House Sergeant-at-Arms Paul Irving, offering conflicting and contentious recollections of how things went wrong. Subscribe to our YouTube channel: https://bit.ly/2TwO8Gm Bloomberg Quicktake brings you live global news and original shows spanning business, technology, politics and culture. Make sense of the stories changing your business and your world. To watch complete coverage on Bloomberg Quicktake 24/7, visit http://www.bloomberg.com/qt/live, or watch on Apple TV, Roku, Samsung Smart TV, Fire TV and Android TV on the Bloomberg app. Have a story to tell? Fill out this survey for a chance to have it featured on Bloomberg Quicktake: https://cor.us/surveys/27AF30 Connect with us on… YouTube: https://www.youtube.com/user/Bloomberg Breaking News on YouTube: https://www.youtube.com/c/BloombergQuickTakeNews Twitter: https://twitter.com/quicktake Facebook: https://www.facebook.com/quicktake Instagram: https://www.instagram.com/quicktake