The council unanimously voted Tuesday night on a plan to to work with the federal government to establish a shelter at the sprawling facility.
The contract with the federal government would start within days and end Aug. 2 at the latest.
Under the plan, the Long Beach Convention Center would temporarily house up to 1,000 children for a period of 90 to 120 days.
The children wouldn't necessarily all be housed at once in the facility. They will receive three meals a day, medical and health evaluations, recreational opportunities and educational services. While Long Beach is providing the facility, the federal government would be responsible for providing and funding those services.
The Biden administration is asking local communities throughout the country to help with sheltering unaccompanied minors who are currently housed in overcrowded Border Patrol facilities.
The city of San Diego has also offered its convention center as a shelter for unaccompanied migrant children.
Long Beach Mayor Robert Garcia said he supports the federal request.
"Long Beach has a proud and long history of welcoming and helping immigrants and refugees. From our Cambodian community to the work done by our churches and faith organizations, we have led with compassion and kindness," Garcia said.
"As an immigrant, I know how important it is to support all people, especially children - and I am proud to support our country in this important work."
Garcia said Monday children could begin arriving as early as next week.
Meanwhile, a rally against the plan was held outside Long Beach City Hall Tuesday to protest the vote, the expansion of any detention center, the incarceration of children and continued criminalization of immigrants.
The Associated Press contributed to this report.
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