The man was taken into custody by Prince George's County police responding to reports that a driver had struck multiple vehicles.
"This is a very fast moving, constantly changing situation," Health and Human Services Secretary Alex Azar said.
Unless the Senate alters its rules, Lev Parnas' GPS device will likely make his attendance in the Senate Gallery impossible.
A terrain awareness and warning system "could have helped" before the helicopter crashed Sunday, a federal investigator said.
There were no immediate reports of damage or injuries. A tsunami threat had been issued but the danger has passed.