SAN DIEGO — A Customs and Border Protection officer in Imperial County has been charged in federal court on accusations that he used unreasonable force on someone who had applied for admission into the U.S. from Mexico. Officer Marcos Valenzuela, 29, was arraigned Wednesday in San Diego federal court, the San Diego U.S. Attorney’s Office said in a news release Wednesday. . The incident happened Aug. 16, 2019, at the Calexico West Port of Entry, about 90 miles east of the San Ysidro Port of Entry in San Diego. It’s not entirely clear what transpired. The indictment has been unsealed, but it did not provide detailed descriptions.