A Ghana court on Wednesday sentenced six people to death by hanging, including three soldiers, for their involvement in an alleged plot three years ago to overthrow the country's government.

The men were arrested in 2021 while testing weapons at an old shooting range in Accra, and intelligence telephone taps led to a blacksmith shop, where they ordered the weapons manufactured, according to court documents.

They had all pleaded not guilty during the trial. Police posted heavily armed units outside the high court for the hearing and sentencing.

One of the lawyers for the six, Victor Adawudu, said the defense team would go to the country's Supreme Court to challenge the decision.

"We will also be going to the Supreme Court for it to look at the evidence," he said.

The high court, however, acquitted police chief Benjamin Agordzo, army officer Colonel Samuel Kodzo Gameli, and one other junior military officer, Corporal Seidu Abubakar.

The six, including a gunsmith and a civilian employee of the Ghana Armed Forces, were charged with conspiracy to commit treason in 2021.

Ghana's attorney general Godfred Yeboah Dame who led the prosecution hailed the outcome of the trial.

According to court documents, the men were arrested at their base in the capital Accra with locally manufactured guns, improvised explosive devices (IEDs) and AK-47 rifles and other ammunition.

Dame said the accused belonged to an association called Take Action Ghana (TAG) and had planned to stage demonstrations to topple the government.

It is the first treason trial in Ghana since 1963 when the first president Dr Kwame Nkrumah was overthrown. Ghana last executed a criminal under the death penalty in 1992 when it returned to constitutional rule.