A Pakistani court convicted five Americans on terror charges Thursday and sentenced each of the men to 10 years in prison.
Prosecutors say the evidence proves the group had been plotting terror attacks against the governments of Pakistan and Afghanistan.
The men have been identified as Ramy Zamzam of Egyptian descent, Waqar Khan and Umar Farooq of Pakistani descent, and Aman Hassan Yemer and Ahmed Minni of Ethiopian descent.
The young Muslims from the Washington, D.C.-area were arrested in Pakistan late last year after their families reported them missing.
"I will right away go to the high court, even to the International Court of Justice, to get these innocent youths justice," said Khalid Farooq, Umar Farooq's father, who was not allowed to watch the trial.
"I have not had a chance to see my son or the other fellows," he said. "I hear they are very frustrated and need to be consoled."
The verdict came the same week in which Pakistani-American Faisal Shahzad pleaded guilty to the attempted bombing of New York City's Time Square in May.