All six were sentenced to either death or life in prison, Reuters reported, citing security forces and family members.
The assault in the early morning hours of Dec. 30 was led by former army private Moudou Nije. Along with several military officers, Nije attacked the presidential palace in the capital of Banju, while Jammeh was out of the country. Some perpetrators were killed at the scene and 5 were arrested along with Nije.
The charges against the conspirators which resulted in 3 death sentences — including for Nije — included treason, conspiracy, mutiny and assisting the enemy. They are allowed a month to appeal the verdicts.
"By all accounts the courts martial that took place were done in secret and the panel consisted solely of military personnel," Jeffrey Smith, a specialist on Africa at advocacy group Robert F. Kennedy Human Rights told Reuters.
US prosecutors say the plot was supposed to overthrow Jammeh and install a Gambian-American housing developer from Texas - Cherno M. Njie, 57 — in his place. Cherno Nije and Papa Faal, of Minnesota, were charged by the US Department of Justice for their role in the attempted overthrow.
Yahya Jammeh has been running the country for more than 20 years. He seized power as result of a military coup in 1994 and justified his actions by coming down on the corruption and authoritarian rule under his predecessor, Sir Dawda Jawara.
Jammeh has been blamed by international organizations and human rights advocates for severe human rights violations and suppression of the media.
