Washington ? The Air Force has dropped three counts in an espionage case against a Syrian-born airman who worked as a translator at the Guantanamo Bay, Cuba, prison camp for terrorism suspects.

The lawyer for Senior Airman Ahmad I. al-Halabi, a supply clerk detailed to the prison, said Saturday that once those charges were removed, “simply the gut of the case was gone.”

Dropped was the single count in the charge that accused al-Halabi of “aiding the enemy,” a capital offense.

Also dropped were counts that dealt with e-mailing information about Guantanamo detainees and committing espionage by transmitting information to unauthorized recipients.

Al-Halabi still faces 17 of the 30 charges filed against him after his arrest in July after nine months as an Arabic translator at the prison. They include other espionage counts, disobeying an order, making false official statements, mishandling classified documents and lying on a credit application.

He is being held at Travis Air Force Base in California, his home base, where his court-martial will be held.

Air Force Lt. Gen. William Welser III, commander of the 18th Air Force at Scott Air Force Base, Ill., convening authority for al-Halabi’s general court-martial, gave no rationale for his decision to drop the charges Friday.

“A convening authority has the discretion to withdraw charges after a case is referred for trial,” Master Sgt. Scott King, a spokesman at Travis, said Saturday in an e-mailed statement.

He said such decisions can follow a commander’s decision that, “based on additional evidence or a change in circumstances, pursuing certain charges may no longer serve to promote justice, assist in the good order and discipline of the armed forces or be consistent with national security.”

Donald G. Rehkopf Jr., al-Halabi’s civilian lawyer, said the impact of Welser’s decision was significant because it went at “the very gut charge of how he was alleged to have done whatever it is they claim or think that he did.”

“The common denominator in those three all involved his allegedly having sent e-mails with classified materials in them. From day one we denied it ever occurred,” Rehkopf said from his Rochester, N.Y, home.