Some 200 tons of supplies could begin arriving as soon as Saturday.
Army Sgt. 1st Class Mark Delacruz, an agent with Army Criminal Investigation Command, faces four criminal charges.
Adm. Phil Davidson defended the Navy in a hearing that also focused on threats posed by China and North Korea.
Rear Adm. Ronny L. Jackson was nominated to be Veterans Affairs secretary until allegations against him emerged.
Mattis submitted a letter of resignation to the president, and now Trump claims he asked for it.
An additional 3,500 U.S. troops will go to the border, Rep. Adam Smith said.
An estimated 747 cadets and midshipmen at the three academies experienced violations, up from 507 two years ago.
The National Guard cannot sustain the number of volunteers needed for border missions, defense officials said.
The plan raised speculation about the potential for military involvement in Venezuela. If enacted, it would mark a major escalation of U.S. involvement in South America.
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