New York City ? A former airport shuttle driver accused of buying beauty supplies to make bombs for an attack on New York City subways pleaded guilty Monday, admitting he agreed to conduct an al-Qaida-led “martyrdom operation” because of U.S. involvement in his native Afghanistan.

Najibullah Zazi told a judge the terror network recruited him to be a suicide bomber in New York, where he went to high school and once worked a coffee cart just blocks from the World Trade Center site.

“I would sacrifice myself to bring attention to what the U.S. military was doing to civilians in Afghanistan,” Zazi said in court.

The Associated Press learned earlier this month that the jailed Zazi had recently volunteered information about the bomb plot in the first step toward a plea deal. His cooperation suggests prosecutors hope to expand the case and bring charges against other suspects in one of the most serious terrorism threats in the U.S. since Sept. 11, 2001.