The head of the ruling Military Council for Justice and Democracy Ali Ould Mohammed Val had declared a "general amnesty to all political prisoners" in the country when he gave his first public address since the 3 August coup.
Saleh Ould Hanenna, jailed on charges of orchestrating failed attempts to oust former president Maawiya Ould Sid'Ahmed Taya was among the 32 military officers and civilians released late on Friday.
Aljazeera's correspondent in the Mauritanian capital, Nouakchott, said a group of Mauritanian officers loyal to Taya who had opposed the military coup, were also freed.
Val said on Friday the amnesty was open to "all Mauritanians found guilty of political crimes or offences, in order to give them the opportunity to participate in building the country with complete freedom".
He added that the military council was determined to democratise Mauritania, and would bar senior government officials from running in planned elections.
"The president and members of the Military Council for Justice and Democracy, as well as the prime minister and members of the government, are ineligible [to stand for presidential and legislative elections]"
Ali Ould Mohammed Val, head,
Military Council for Justice and Democracy in Mauritania
He said the military council had committed itself to "creating conditions conducive to a democratic, open and transparent election and restricted its period of government to not more than two years".Issuing a decree, he said "the president and members of the Military Council for Justice and Democracy, as well as the prime minister and members of the government, are ineligible" to stand for presidential and legislative elections.
The aim is to guarantee "the absolute neutrality of the state apparatus and administration" during an electoral process decided upon in the framework of the democratic transition process, Val said.
In another development, the Mauritanian attorney-general announced the prosecution of two Mauritanian central bank senior officials who were accused of fraud involving about $5 million, Aljazeera learned.
The central bank had earlier accused the two officials - the treasury inspector and treasury secretary - of siphoning the money between 1996 and 2001.
The two were arrested about two weeks ago.
Minister in Qatar
Separately, Mauritanian Oil and Energy Minister Mohammed Ali Ould Sidi Muhammad visited Qatar on Friday as part of a tour of Gulf states.
Qatar's Shaikh Tamim met the oil
and energy minister of Mauritania
Sidi Mohammed met Qatar's heir apparent, Shaikh Tamim bin Hamad Al Thani.
He delivered a message from Val addressed to the Qatar Amir Shaikh Hamad bin Khalifa Al Thani.Shaikh Hamad had told Aljazeera that he commended the orientation of the new government in Mauritania, and expressed hope that the military coup would serve as a prelude for a democratic era for its people.
The message dealt with bilateral relations and recent developments in Mauritania.
"What is happening in Mauritania is an internal affair, and the statements by its military leaders indicate that the country is heading toward democracy," the Qatari leader said.
He added that the decision to offer asylum to deposed Mauritanian leader Taya would not affect relations between the two countries.