The defendants include Jamaat-e-Islami chief Matiur Rahman Nizami, former State Minister for Home Lutfozzaman Babar, and the United Liberation Front of Assam's military wing chief Paresh Barua, Bdnews24.com reported.
Two former generals were also sentenced to death.
They have also been fined $6,400.
The defendants were charged under the Arms Act for illegal possession of firearms and the Special Powers Act for weapon smuggling.
The verdict comes almost 10 years after authorities seized 10 truck loads of weapons and ammunition, which were smuggled into Chittagong.
About 1,500 boxes of sub machine guns, assault rifles, rocket launches, hand grenades, bullets and other weapons were found.
The arms were being transported to UFLA hideouts.