BOSTON -- Two men accused in a terror plot to kill Americans face new federal charges that they conspired to provide personnel, advice, assistance and other services to Al Qaeda.

A grand jury on Thursday added charges of conspiring to provide material support to a designated foreign terrorist organization in a superseding indictment against 27-year-old Tarek Mehanna of Sudbury, Mass., and 28-year-old Ahmad Abousamra. Authorities say Abousamra, who used to live in Mansfield, Mass., is now in Syria.

The men face up to 15 years in prison and a fine of $250,000 if convicted of the latest charge.

When reached by phone, Mehanna's lawyer, J.W. Carney Jr., did not comment.

The suspects already face a 10-count indictment. Prosecutors say the men conspired to kill American troops in Iraq, assassinate two unnamed U.S. politicians and shoot shoppers in U.S. malls.

...Ahmad Abousamra is the oldest son of Abdul-Badi Abousamra, former vice president of the Boston branch of the Muslim American Society, which operates the largest Islamic center in the Northeast...