Haroon Syed had admitted planning terrorist acts at an earlier court hearing.
Today, judge Michael Topolski said 19-year-old Syed had been intent on "carrying out an act of mass murder in this country." He sentenced him to life with no chance of parole for 16 1/2 years.
Prosecutors said Syed tried to buy weapons and explosives online from an extremist named "Abu Yusuf," who was actually a series of British intelligence agents.