Hundreds of detainees from US Customs and Border Protection (CBP) facilities in Texas and elsewhere are being flown to San Diego for processing, the agency said on Friday.
Border officials said they are developing plans to fly potentially thousands of migrant families to other places away from the southern US border with Mexico.
The agency said the number of people apprehended at the border since October 1 was nearly 520,000, the highest in a decade.
In the past week, there was an average of 4,500 arrests a day.
This is making it difficult to process and release family units within 20 days of their arrival at a detention centre, as required by law, the CBP said in a statement.
US President Donald Trump earlier this year declared the immigration influx a national emergency, which allowed him to circumvent Congress to redirect more than $6bn in funding to start building the border wall that he campaigned on in the 2016 presidential election. His move has been challenged in courts.
Three flights a week will arrive in the San Diego area from the Rio Grande Valley carrying approximately 130 people per flight, a CBP official at the San Diego office said.
“We’re in the middle of a humanitarian crisis and the numbers in Texas are staggering so the BP is helping out in those sectors to more efficiently process these folks,” said the official, who declined to be identified.
Flights operated by the US Immigration and Customs Enforcement agency (ICE) will land at San Diego International Airport and the detainees will be moved to the eight Border Patrol stations in the San Diego sector.
“They will be housed properly inside,” the official said.
The program has no end date and no unaccompanied children will be on the flight.
The CBP statement said the border officials are also busing people to El Centrol from Yuma and to Laredo from the Rio Grande Valley. It did not say which other cities might receive migrants.
Media reports say the agency was considering flights to Detroit, Miami and Buffalo, New York, where the agency has facilities.
Trump last month threatened to send migrants to so-called sanctuary cities such as New York and San Francisco, which generally give undocumented immigrants safe harbour by refusing to use their resources to help enforce federal immigration laws that could lead to deportations.
In the past week, border authorities have averaged 4,500 apprehensions a day and facilities aren’t equipped to care for the influx of children, the CBP statement said.
Since December 21, ICE has released approximately 180,000 family members into places in the US.
“Whenever possible, the releases have been coordinated with local non-governmental organisations (NGOs). As NGOs have reached their capacities, CBP has released family units at transportation hubs during daylight hours when the weather does not endanger those released,” the statement said.
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