Sixteen people arrested in Burkina Faso for planning an alleged coup against President Blaise Campaore are to be charged before a military tribunal for "conspiracy against state security," the government said on Friday.
The alleged mastermind of the plot, Captain Luther Diapagri Oualy, will also face treason charges, it added.
"The results of our investigations allow us to have no doubt about the reality of the destabilisation attempt and the obvious involvement of foreign countries," Abdoulaye Barry, the prosecutor general, told a news conference in the capital, Ouagadougou, on Friday.
He once more declined to name the countries involved, saying it would be up to the presiding judge at the trial to do give full details.
Barry said earlier this month that Oualy held meetings with officials in Cote d'Ivoire and Togo in September, but both countries have denied any involvement in the conspiracy.
Barry said investigations were now complete and the plotters would be tried in a military court since 14 of them were soldiers. If found guilty, they faced prison terms ranging from five years to life imprisonment, he added.
The highest ranking soldier being held is Commander Bernadin Poda who was working in the accounts department of the army. He is suspected to have siphoned out money from the army to finance preparations for the coup.
One of the soldiers arrested earlier this month, Sergeant Moussa Kabore, who was born in neighbouring Cote d'Ivoire, died in custody. The government said he hanged himself in his cell on 8 October.
Barry said on Friday he would not hesitate to name the foreign backers of the coup plotters if necessary. "I am talking facts. If some of facts point to them [the countries involved] I will say them, irrespective of political considerations, which I am not interested in. I am working within the domain of law."
There is no love lost between the governments of Cote d'Ivoire and Burkina Faso. Ivorian President Laurent Gbagbo has repeatedly accused Campaore of supporting rebels who have occupied the northern half of Cote d'Ivoire for the past 13 months.
The two civilians being held are pastor Pare Israel and Norbert Tiendrebeogo, chairman of the opposition Social Forces Front (FFS) party, who was arrested on Monday.
Tiendrebeogo was a close ally of former president Thomas Sankara who was killed in the coup that brought Campaore to power in this poor landlocked country in 1987.
FFS deputy leader Brice Yogo told IRIN earlier this week that Tiendrebeogo was summoned to the police headquarters for questioning on Monday and was subsequently detained.
A coalition of opposition parties known as G14 has petitioned the government to free Tiendrebeogo immediately.
The Burkina Faso Movement for Human and People's Rights has complained that many of those detained have been held without charge for more than 20 days, far longer than the three days allowed by law.