Continuing a push in defiance of President-elect Donald Trump, President Obama has transferred four more terrorism detainees out of the Guantanamo Bay detention facility, lowering the prison population to 55. The four detainees, natives of Yemen, have been transferred to Saudi Arabia, the Pentagon said. They were captured during the Afghanistan war and had been imprisoned without trial for about 15 years. Human Rights First praised the move and encouraged Mr. Obama to accelerate the pace of transfers before Mr. Trump is inaugurated on Jan. 20. Another 14 detainees have been approved for transfer. “While today’s transfer is encouraging, the president must act swiftly if he is to transfer the remaining detainees who have been unanimously cleared by national security agencies,” said Human Rights First’s Raha Wala. “The president has signaled time and again that closing Guantanamo is a priority for his administration; though it seems unlikely he is to complete that goal, he can and should continue to dwindle the population.” White House press secretary Josh Earnest said Thursday that more transfers are likely before the president leaves office. Mr. Trump has said he would keep open the prison at Guantanamo Bay and send more terrorism suspects to the facility.