WASHINGTON — Sen. Ron Johnson (R-Wis.), chairman of the Senate Homeland Security and Governmental Affairs Committee, questioned Department of Homeland Security Deputy Secretary Alejandro Mayorkas Thursday on the root cause of the long waiting lines that travelers are experiencing at airports in Wisconsin and across the country.

Mayorkas testified that three general factors are to blame: enhanced security, an increase in travel volume and a reduction in personnel.

Watch the full exchange here.

COMING UP: Chairman Johnson will be holding a hearing in the Senate Homeland Security and Governmental Affairs Committee on Tuesday, June 7, 2016 to further examine TSA’s response to long lines at U.S. airports and to evaluate their actions to secure the U.S. aviation system, particularly in light of the incident involving EgyptAir Flight 804.