He also showed reporters an ammunition box filled with ID cards and documents he claimed belonged to the rebels.
Many of the documents were written in Arabic, while some ID cards were those of men belonging to the Rally of Forces for Change (RFC), a rebel group led by Timane Erdimi, a nephew of Idriss Deby, the Chadian president.
Bachir did not explain why the government had waited for more than a week after the February 2 attack on Ndjamena to present the prisoners.
Deby's government accuses the Sudanese government of supporting the rebel coalition in Chad in order to export so-called "Arab Islamic militancy" across the Sahara.
Bachir said: "Even those who are Chadian are not really Chadian, they are mercenaries in the pay of Sudan."
"They came to invade our country, they were sent by Omar al-Bashir [the Sudanese president] to come and destabilise not only Chad, but all of Africa."
The minister said the captives would be treated as prisoners of war, even those who seemed to be under 18.