US President Donald Trump announced Tuesday he would keep Guantanamo Bay open after his Democratic predecessor, Barack Obama, tried unsuccessfully to close the prison. "I just signed an order directing Secretary Mattis to reexamine our military detention policy and to keep open the detention facilities at Guantanamo Bay," Trump said, in his State of the Union address to Congress, in keeping with a campaign promise. Under president George W. Bush, the US military hastily constructed a prison camp on Guantanamo Bay, located on the US naval base on the eastern tip of Cuba, in the months following the US-led invasion of Afghanistan after the September 11, 2001 attacks. At first, inmates were held in cages and fenced in with razor wire, and conditions for the orange jumpsuit-clad detainees provoked a global outcry in 2002. That early facility, known as Camp X-Ray, was soon replaced with more permanent structures and today, Guantanamo Bay consists of numerous high-security prison buildings. At the height of its operations after 9/11, the facility held 780 people, detained mostly for their alleged ties to Al-Qaeda and the Taliban. Since then, hundreds have been transferred back to their home countries or other places. As a presidential candidate, Trump vowed "to load it (the prison) up with some bad dudes." Since he became president a year ago, there is no indication any new prisoners have arrived.