NYPD to question man suspected of supplying parts to assemble AR-style rifle used

Part of the gun used by a Las Vegas man to kill four people last night in a Midtown Manhattan office building is under investigation as being provided by an associate. NBC News National Law Enforcement and Intelligence Correspondent Tom Winter breaks it all down. Retired NYPD Detective Marq Claxton and former NYPD Officer Jillian Snider join Erielle Reshef to respond.