Chad's President Idriss Deby on Monday freed nearly 60 detainees considered political prisoners by rights groups as part of a general amnesty for former rebels, the country's justice minister told AFP.
Those released included Moussa Tao, arrested in 2013 on a conspiracy charge; and Colonel Haroun Bata and about 10 Chadian "mercenaries" accused of having organised an attempted coup in Equatorial Guinea a year ago.
"We conducted a ceremony to release 58 prisoners as part of the general amnesty," said Justice Minister Djimet Arabi.
But former rebel Baba Ladde, jailed for eight years earlier this month, was not on the list, the minister said.
"He can still be subject to a reduced sentence or a presidential pardon," he said.
Rights groups in Chad, who have on several occasions called for the full application of the amnesty, declared in May, welcomed the news.
Most of those released had been held for several months without trial, they said.
At the beginning of December, 12 other prisoners had been released, said Jean-Bosco Manga, spokesman for the ACAIAT group, a citizens group campaigning for a full amnesty.
Arabi said the total number of prisoners freed came to 70 and cases were still under consideration.