US Defence Secretary James Mattis has confirmed that tent camps will be constructed on two military bases in Texas, in order to house immigrants detained under the Trump administration's "zero tolerance" immigration policy.

Two US defence officials identified the bases as Fort Bliss and Goodfellow Air Force Base to the Associated Press earlier on Monday.

The officials said unaccompanied child immigrants would be sheltered at one base, and the other would be used to house family detainees. The land would be supplied by the Defence Department, but the facilities would be run by outside organisations.

Spokespeople at the military bases directed The Independent to HHS, which did not immediately respond to a request for comment.

The Pentagon said last week it was preparing to house 20,000 migrants, as the Trump administration's new "zero tolerance" policy caused the number of people in detention to soar. The policy requires anyone caught crossing the border illegally to be held for prosecution.

Trump's US immigration policy explained

The plans reveal the extent to which the US military is being used to handle the influx of immigrants in detention. Mr Mattis told reporters on Monday that he found housing immigrants to be a "quite appropriate" function for the Defence Department to serve.

"This is something that we can do," he said, according to NPR. "Again, whether it be refugee boat people from Vietnam, people who've been knocked out of their homes by a hurricane – absolutely, it's appropriate the military provide logistic support however it's needed."

The US Navy was also reportedly considering the construction of tent cities housing up to 47,000 immigrants in California, Arizona, or Alabama last week, according to an internal draft memo first obtained by Time. The memo suggests each tent camp should be built to last between six months and a year, and would cost about $233m (£176m) to construct and operate for a six-month time period.

‘Families belong together’ protests over Trump immigration policy Show all 8 1 /8 ‘Families belong together’ protests over Trump immigration policy ‘Families belong together’ protests over Trump immigration policy Mishawaka, Indiana AP ‘Families belong together’ protests over Trump immigration policy Washington DC AFP/Getty Images ‘Families belong together’ protests over Trump immigration policy New York Mayor Bill De Blasio speaks in Tornillo, Texas alongside the many other US mayors who have called for detained immigrant children to be reunited with their families AP ‘Families belong together’ protests over Trump immigration policy Albuquerque Mayor Tim Kelle leaves a teddy bear as a gift for detained immigrant children in Tornillo, Texas AP ‘Families belong together’ protests over Trump immigration policy Seattle Mayor Jenny Durkan and Los Angeles Mayor Eric Garcetti leave sandals as gifts for detained immigrant children in Tornillo, Texas AP ‘Families belong together’ protests over Trump immigration policy San Diego, California EPA ‘Families belong together’ protests over Trump immigration policy US embassy, Mexico City AFP/Getty Images ‘Families belong together’ protests over Trump immigration policy San Diego, California EPA

The announcement of the new tent camps came after Mr Trump signed an executive order requiring migrant families to be housed together while facing charges. More than 2,000 children were separated from their parents at the border under a previous policy, which required children caught crossing between points of entry to be turned over to Health and Human Services (HHS).

Mr Trump directed the Defence Department to aid in identifying or constructing facilities in which to house the families last week. But officials worried that the government would not have enough beds to house the influx of detainees under the zero tolerance policy – much less house families together.

US Immigration and Customs Enforcement (ICE) currently has 3,326 beds in family detention centres, according to a 2018 report to Congress. More than 2,600 of those beds were full as of 20 June, Politico reported. HHS officials told The Independent in May that their child immigrant shelters were 95 per cent full.

A newly constructed temporary tent shelter for immigrant children in Texas was already close to capacity on Monday, officials told the Associated Press. More than 320 children between the ages of 13 and 17 were being held at the facility, which was built to house 360.

US congressman Will Hurd told Texas Monthly last week that the facility appeared safe and well-run, and that case workers were working to get the children placed with sponsors inside the country.