Eighty minors who had been arrested and held in a desert prison following deadly protests in Chad in October have been given bail, public prosecutor Moussa Wade Djibrine said on Thursday.

"A request for (their) provisional release was filed and the judge accepted it," he said, adding that proceedings against the minors were still "ongoing."

Hundreds of people were detained following bloody protests against Chad's ruling junta, of whom 262 have been handed jail terms of up to three years.

Outlawed demonstrations were held on October 20 to mark the date when the military had initially promised to cede power -- a timeline that has now been extended by two years.

Around 50 people died, including 10 members of the security forces, according to an official toll.

But opposition groups say the real count was much higher, and allege unarmed civilians were massacred.

Strongman General Mahamat Idriss Deby Itno accused the demonstrators of "insurrection" and attempting to stage a coup.

The authorities have said 601 people, including 83 minors, were arrested in the N'Djamena area alone and taken to Koro Toro, a high-security jail located in the desert 600 kilometres (375 miles) from the capital.

A total of 401 people were put on trial in a court in the jail, in proceedings that lawyers boycotted in protest.

After a four-day trial, 262 were jailed for between two and three years, 80 were given suspended terms and 59 were acquitted, the prosecutor said on Monday.

Deby, 38, took power when his father, Idriss Deby Itno, who had ruled the arid Sahel state for 30 years, died during an operation against rebels in April 2021.