Zahid Iqbal, Mohammed Sharfaraz Ahmed, Umar Arshad and Syed Farhan Hussain -- aged between 22 and 31 -- pleaded guilty in March to engaging in conduct in preparation for acts of terrorism.
Prosecutors said they downloaded files containing instructions for an attack, bought survival equipment and collected money for terrorist purposes. They also admitted "facilitating, planning and encouraging" overseas travel for terrorist purposes.
Iqbal and Ahmed were sentenced Thursday at London's Woolwich Crown Court to 16 years and 3 months in jail. Arshad got a sentence of six years and nine months, while Hussain received five years and three months.
Take ABC13 with you!
Download our free apps for iPhone, iPad, Android and Blackberry devices