Syria's state news agency SANA said of the 672 inmates released on Saturday, 588 were let go from the main prison in Damascus. Ninety-one women were among those freed.

Justice Minister Hisham al-Shaar said the prisoners had promised to accept the state's authority.

"They have been released after promising not to do anything against the nation's security or stability," SANA cited him as saying.

Their freedom coincided with the Muslim holiday of Eid al-Fitr, which this year begins Sunday and marks the end of the holy month of Ramadan.

'National reconciliation'

Al-Shaar used the term "national reconciliation," which is often used to describe deals with rebel groups who either disarm or leave besieged areas of the country for other insurgent-held areas.

"It also aims at giving another chance to those who were previously misled so that they can lead a normal life again," the official added, in reference to those who took part in the 6-year armed rebellion against the regime of Syrian President Bashar Assad.

Another amnesty took place close to Raqqa, the so-called "Islamic State" (IS) armed group's de-facto capital in Syria, which the US-backed Syrian Democratic Forces hope to fully recapture in weeks.

A council of rebel groups, set up to rule Raqqa when it falls, announced on Saturday it was releasing 200 low-ranking IS members that had been captured in recent months. The release came in response to a request from tribal leaders in the region. The Observatory said the IS members were not fighters, but rather held jobs in the civilian administration.

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Prisoners sided with rebels

In relation to Saturday's mass release by the Syrian government, SANA did not say what the detainees had been in prison for, but some of those freed told Reuters they were arrested for actions they took against the government.

Among those let go in Damascus was 45-year-old Abdul-al-Rahman Ali who used to finance opposition fighters.

"I was wrong and every person makes mistakes. I have repented and returned to embrace my homeland," he said.

A mother wiped away her tears as she waited for her son who had been jailed for more than three years.

"I am glad for the release of my son," said the woman who identified herself as Um Akram, outside the headquarters of Assad's ruling Baath party in Damascus where some prisoners were freed.

The lucky ones

According to human rights groups, tens of thousands of people have been detained by the Syrian government since the civil war broke out in 2011. Many of them have been held without trial for political reasons.

Reports suggest many thousands have been tortured and killed during their time in prison, although the Syrian government has denied that.

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Elsewhere on Saturday, Israel launched airstrikes inside Syria in apparent retaliation for the firing of 10 projectiles from the war-ravaged country which landed in the Golan Heights.

The Syrian Observatory for Human Rights, a monitoring group, said Israeli warplanes had targeted a Syrian army position in the area. Two armored vehicles were destroyed, the watchdog added.

Pull Russia-US back from the brink

Meanwhile, United Nations envoy to Syria Staffan de Mistura told a German newspaper he was hopeful that the upcoming G20 summit in Hamburg early next month will give a "boost" to the chances of peace in Syria.

He told Tagesspiegel in an interview to be published on Sunday, "It is essential that the US and Russia agree for there to be peace in Syria."

His comments come amid concerns of a direct confrontation between Russia and the US in the war-ravaged country after US jets last week downed a Syrian jet. Russia, who backs Assad's regime, has vowed it will treat any US plane flying west of the Euphrates as a potential target.

The G20 takes place on July 7 and 8 just two days before the next round of Syrian peace talks.

mm/sms (AP, dpa, Reuters)