DESERT HOT SPRINGS, Calif. (KESQ) - A resident of Desert Hot Springs is speaking out after what he describes as a distressing experience at the U.S.-Mexico border. Tony Johnson, a retired U.S. Marine Corps veteran in his 50s, says he was recently detained at the San Ysidro Port of Entry after returning from Mexico, where he had gone to seek medical treatment. Johnson, who receives care through the U.S. Department of Veterans Affairs for PTSD, an…