According to the group, 11 security personnel were arrested in the blaze which left at least 45 migrants dead.
Yemen’s Houthi rebels admitted their forces started a fire that killed 45 people at a migrant center earlier this month, saying more than a dozen soldiers and officials were being punished.
Houthi security forces responded to a protest at a Sana’a detention center on March 7 by throwing three tear gas canisters without obtaining permission from their command, according to a statement released by the rebel Saba news agency on Saturday evening.
“One of the three [canisters] landed on a foam mattress, which caused a fire that quickly spread, ”he said.
The statement said 11 security personnel had been detained, along with a number of senior officials, and would be tried in court.
The rebels said 45 migrants and refugees, mostly Ethiopians, were killed and more than 200 injured in the incident.
The Houthis, who are locked in a six-year conflict with the internationally recognized Yemeni government, last week expressed “deep regret” for the incident at the Sana’a detention center and vowed to investigate.
The United Nations had also called for an independent investigation into the fire.
The UN envoy for Yemen, Martin Griffiths, told the Security Council that “the extraordinary and horrific fire” had reminded the world “of the plight of the migrant community”.
Human Rights Watch said detainees protested overcrowding at the center when camp guards rounded up hundreds in a hangar before two projectiles were fired at the building.
Images of the aftermath, which the AFP news agency obtained from a survivor, showed dozens of charred bodies piled on top of each other and strewn on the ground. One person was heard screaming in prayer.
Iranian-backed rebels control much of northern Yemen, including the capital, Sana’a, which was captured by the Saudi-backed government in 2014, sparking the devastating conflict.
Despite the warnings, migrants and refugees from the neighboring Horn of Africa continue to pass through war-torn and impoverished Yemen, in search of a better life in the wealthy Arab Gulf neighboring states.