The United States is building up forces in five locations in Puerto Rico, including at a Navy base that was closed in 2004.
More aircrafts, combat vehicles and landing craft air cushions have been sent to the US island since November. The US also has number of ships in the region, including the aircraft carrier USS Gerald R Ford.
Former Vice Admiral and Deputy Commander of US Central Command, Robert Harward, spoke to the BBC about some of the military hardware being brought to shore.
Video by Meiying Wu
Disclaimer : This story is auto aggregated by a computer programme and has not been created or edited by DOWNTHENEWS. Publisher: BBC
