Special judge Kauser Edappagath found the convicts guilty under the Unlawful Activities Prevention Act, the Explosives Substances Act and the Indian Penal Code.
The NIA said the SIMI members were given arms training, including bomb-making at the camp in Kerala's Wagamon, 185 kilometres from state capital Thiruvananthapuram. The prosecution said the SIMI members met in Indore in November 2007 and decided to run training camps in some states.
Two of the convicts came to the court today, while the others who are in jails in Ahmedabad, Bhopal and Bengaluru attended the proceedings via video conference.
The NIA said the SIMI members organised training camps in Karnataka, Madhya Pradesh and Gujarat from December 10 to 12, 2007. One of the camps was the one in Kerala's Wagamon.
In February last year, SIMI chief Safdar Hussain Nagori and 10 others were sentenced to life in a 2008 sedition case by a special court in Indore.
The SIMI was the student wing of the Jamaat-e-Islami Hind, which split from the main organisation in 1981. The organisation saw a radical shift in its ideology in the 1980s, although SIMI claims the organisation was started in order to work for the welfare of Muslim youth.