Yemen's rebels on Monday released scores of detainees they had rounded up and held for years in rebel-controlled territory, a development that raised hopes of reviving stalled peace talks between the warring sides.
The International Committee of the Red Cross said the Iran-aligned rebels, known as Houthis, freed 290 detainees.
Franz Rauchenstein, the ICRC's chief in Yemen, said the Red Cross facilitated the release following a request from the Houthis. He expressed hope this would open the door to "further releases to bring comfort to families awaiting reunification with their loved ones."
Most of the prisoners were taken in raids since 2014, when the rebels overran the capital, Sanaa, and much of the north, pushing out Yemen's internationally recognized government and ushering in the civil war that has killed tens of thousands of people.
A Saudi-led coalition intervened in the conflict in 2015 and has since waged war against the Houthis in an effort to restore the government of President Abed Rabbo Mansour Hadi to power. The fighting in the Arab world's poorest country has also left millions suffering from food and medical care shortages and pushed the country to the brink of famine.
The ICRC said Monday's release included 42 survivors of an attack earlier this month by the Saudi-led coalition on a Houthi-run detention center in the southwestern province of Dhamar. At least 130 people, mostly prisoners, were killed in that attack, according to Yemeni medics.
In Sanaa, the Houthis announced they released 350 detainees on Monday, including three Saudis.
ICRC official Sarah al-Zawqari told The Associated Press that the Red Cross interviewed and facilitated the release of 290. "There could have been more prisoners released but if that's the case, that happened without our support," she added.
Abdul-Qader el-Murtaza, a rebel official in charge of prisoners' affairs, called on the United Nations to pressure the Saudi-led coalition to "take a similar step" and free its detainees in the war.
One of the prisoners freed by the rebels, Abu Hossam, said he was taken in the port city of Hodeida two years ago. "They were miserable days," he told the AP.
Another prisoner, Salman al-Ibby, said he was detained in the Houthi-held city of Ibb five years ago, at the start of the war. Both Mr. Hossam and Mr. Ibby declined to say more about their years in captivity, fearing reprisals.
The U.N. special envoy for Yemen, Martin Griffiths, called on "all parties to ensure the safe return of the released detainees to their homes."
He also invited the warring sides to meet at "the nearest opportunity and to resume the discussions" that began last year in Stockholm, Sweden, where both sides signed a U.N.-brokered peace deal in December that included an exchange of more than 15,000 prisoners. But the deal was never fully implemented.
This story was reported by The Associated Press. Samy Magdy and Jamey Keaten contributed to this report.