Bahrain's Independent Commission of Inquiry (BICI) - looking into the Gulf island's crackdown on protesters as part of the Arab Spring - welcomed a government decision to release 137 detainees Tuesday, DPA reported.
The group had been charged with misdemeanours and were awaiting trial before the military courts. Their cases had been transferred from the military courts to civilian courts following a royal decree and at the request of BICI.
Two of the released detainees are former lawmakers, Mattar Mattar and Jawad Fairuz, members of the al-Wefaq National Islamic Society.
Following the introduction of martial law and the deployment of Gulf forces to the island, mainly from Saudi Arabia and United Arab Emirates, in mid-March more then a thousand people - mainly Shiites - were detained, according to Bahraini officials.
Among those who were detained were 47 doctors and medics accused of conspiring with protesters. The majority had been released since then, but 14 remain in custody.
The release came as news that one of the detained doctors had suffered a stroke while in police custody and had to be rushed to hospital.
However, BICI chair, Mahmoud Cherif Bassiouni, came under fire from relatives of some of those protestors detained for allegedly telling the media that government violations did not represent a "systematic targeting."
Several families gathered outside the commission offices in Manama to protest the comments.
"Our work is ongoing and contrary to what some who raise questions about us may say, we have not prejudged anything and we are fortunate to have the confidence of many on all sides of all issues," Bassiouni said.
"We are committed to truth, to the defense of human rights, and to upholding the rule of law".
According to Bassiouni the investigative teams have made a number of visits to prisons, detention centres and police stations, and hospitals, many of which have been unannounced.
"They have recorded and collected the testimonies of all the prisoners with whom they've met, as well as their families, including documenting reports of cases of mistreatment and torture," he said
"We are continuing our investigation of reports of mistreatment and torture, and we will soon have a team of forensic medical experts from outside the country come in to look at all individuals who have complained of physical mistreatment and torture."
More than 2,500 people were sacked from their jobs for allegedly taking parts in Bahrain's protests.
Bahrain lifted its two-and-half month old martial law on June 1st. Protests demanding political reform and greater freedoms in Sunni-ruled, Shi'ite majority Bahrain began on February 14.
Human Rights Watch, Amnesty International, and Doctors Without Borders among other rights groups had criticized the Bahraini government crackdown.