OAKLAND — A United States Coast Guard commander was charged with three counts of illegal importation of controlled substances Wednesday, a U.S. Justice Department spokesman said.

According to a complaint, James Silcox III, 41, received three shipments of Tramadol, a controlled substance and narcotic, to post office boxes over the summer.

On July 11, an 865-gram package from Singapore headed for an Alameda post office box was flagged by U.S. Customs and Border Protection officers at the U.S. Postal Service’s international mail facility at New York’s John F. Kennedy International Airport.

According to a probable-cause statement, the package came from Delta Shipping, a “repeat-seizure violator identified with over 300 seizures of narcotics,” and import-history research and records checks link Silcox to at least eight seizures of drugs, including Tramadol, Modafinil and cocaine, headed to Bay Area post-office boxes.

Officers at the postal service’s San Francisco airmail facility intercepted another 650 200-milligram tablet Tramadol package from Singapore on August 28, before receiving another package Sept. 13 that held 458 grams of Tramadol.

After law enforcement officers swapped out the August package’s Tramadol for substitute material, they delivered it to Silcox’s post office box Monday. He picked up the package the same day, and officers arrested him Tuesday at his Coast Guard Island residence.

In an interview at that time, Silcox told a Homeland Security Investigations officer that he began purchasing Tramadol online two years ago from a person he believed was based in Singapore. When agents received consent to search Silcox’s car, they found Tramadol pills and the swapped substitute material from the earlier shipment.

Silcox was released on a personal recognizance bond after appearing in San Francisco federal court Wednesday morning, and he will return Sept. 26 to identify counsel and attend a preliminary hearing before U.S. Magistrate Judge Kandis Westmore.

He faces up to five years in prison and a $250,000 fine for each violation, but federal sentencing guidelines will ultimately affect any imposed sentence.

Assistant U.S. Attorney Sarah Griswold is prosecuting the case, which came from an investigation by the Homeland Security Investigations; the High-Intensity Drug Trafficking Area-Transnational Narcotics Team; the U.S. Postal Inspection Service; the Department of Homeland Security Office of Inspector General; and the Coast Guard Investigation Service.

Contact George Kelly at 408-859-5180.