"A total of 230 detainees were released from the Abu Ghraib prison, Camp Bucca and Camp Suse," a justice ministry spokesman said, referring to the three US-run detention centres.
The release ceremony took place at Abu Ghraib prison and detainees were addressed by Sunni Vice President and Iraqi Islamic Party leader Tareq al-Hashemi who gave each of the prisoners 200 dollars.
In his speech, Mr Hashemi emphasised that efforts were ongoing to get the rest of the detainees in US-run prisons freed since they had been detained on wrongful information.
Accompanying him was Omar al-Juburi, the party's human rights representative and a number of other party officials and tribal leaders.
With most of the detainees being Sunni Arab, Mr Hashemi and other Sunni politicians have made the issue one of their political causes.
Shortly before Mr Maliki's announcement to release 2,000 prisoners, Sunni politician Adnan al-Dulaimi suggested prisoners be released to ease tensions between Sunnis and Shiites.
Detainees unaware
Many of the detainees said they had no idea why they had been held or insisted they were innocent of all the accusations levelled against them.
"I went to a funeral and then I ended up here," said Awad Jassim Mohammed, 59, as he leaned on his cane.
Abdel Karim Yassin, from the main northern city of Mosul, said he was arrested a year ago and still doesn't know why he was detained at Camp Bucca, near the Saudi border.
He complained bitterly about the time he had spent incarcerated. "If you are educated and you came here, you leave illiterate and stupid," said the Master's degree holder.
Arkan Abdallah, a 17-year-old student who was detained while working on a farm was more optimistic about the situation and praised the prime minister's move.
"It's a good start and hopefully the government will make it," he said, despite the cost to his studies of his time in detention. "I probably missed most of my tests and exams," he said.
Most of the inmates boarded buses to take them to the Baghdad bus terminal, while some waited overnight to fly to more northern destinations for safety reasons.
Earlier this week, 594 detainees were released from various prisons after Mr Maliki announced that a total of 2,000 would be freed as a gesture to promote national reconciliation.
More than 28,500 detainees are still being held in Iraqi and US-run detention centres.