Former White House official sworn in as DHS secretary

Kirstjen Nielsen has been sworn in as the next Homeland Security secretary.
The ceremony took place at the White House today. Reporters were not invited to document the occasion.
Nielsen says in statement that it's her "greatest honor to serve" in the role.
She says the country faces "a complex threat landscape that is constantly evolving" and that she will do her "utmost to ensure that the Department meets the threats of today and tomorrow."
Nielsen formerly served as deputy White House chief of staff and as former DHS Secretary John Kelly's No. 2 at the department.
Secretary Elaine Duke has been serving as acting secretary since Trump tapped Kelly to be his chief of staff.