The tribunal sentenced Julius Ayuk Tabe and nine others on Tuesday. The defense counsel boycotted the trial, claiming bias. Defense lawyer Edwin Fongo said they will appeal the sentence.
Those sentenced were arrested in neighboring Nigeria and extradited to Cameroon in January 2018 along with 46 others alleged to have supported a separatist Anglophone state in Cameroon. Armed conflict over Cameroon's separatist movement since 2016 has killed more than 2,000 people, according to the International Crisis Group.
Rights groups have criticized the life sentences, saying they are an abuse of the rule of law and will lead to more violence.
Copyright 2019 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.