The first order of business for U.S. Troops on the border was to install concertina wire along the Nogales border at the DeConcini Port of Entry.
According to the Army North Media Operation Center, there are currently 1,500 troops stationed at Davis Monthan Air Force Base.
They believe the caravan originating in Central America is still at least two weeks away.
People living on both sides of the border say they are shocked at how the border has transformed and say it looks like a war zone with military personnel patrolling the area.
On the caravan coming from Central America, people who live in Mexico say they differ in opinion.
While some worry about thousands of people coming into the city at once, others would rather offer a helping hand.
"We have to give them a helping hand like the U.S. has helped us in Mexico for many years. Now its our turn and we have to welcome them. They're human beings who are fleeing their countries out of necessity."
Military officials say an increase of troops in Arizona isn't expected. As of now, the new wire on the fence is the only way they'll be reinforcing the border.