BROOKLYN - (AP) - Federal authorities expect to file more chargesin an alleged plot by an al-Qaida associate to attack New York Citywith homemade bombs, a prosecutor said Thursday.

Assistant U.S. Attorney Jeffrey Knox told a judge the chargeswould be contained in a new indictment against Najibullah Zazi, aColorado airport van driver arrested earlier this year on chargesof conspiring to use weapons of mass destruction.

"I think it's likely there will be additional charges," Knoxsaid at a pretrial hearing in federal court in Brooklyn. "Theinvestigation continues."

The prosecutor didn't specify the charges, or say whether theindictment would name more defendants. He called the evidence inthe case "voluminous."

Zazi, who sat motionless at the defense table during the15-minute hearing, was ordered to return to court on Feb. 16.