The number of people detained by Immigration and Customs Enforcement has hit an all-time high, according to recent statistics reviewed by The Daily Beast.

That massive increase in detentions by the highly controversial agency has prompted questions from rights groups about how Immigration and Customs Enforcement (ICE) obtained the money to place into its custody 4,000 more people than Congress has funded. Earlier this year, when facing a similar shortfall, the Department of Homeland Security, ICE’s parent organization, quietly moved nearly $100 million dollars out of other areas of its budget, including the Federal Emergency Management Agency, prompting an outcry from a prominent senator.

That senator, Oregon Democrat Jeff Merkley, told The Daily Beast it was unsurprising that the Trump administration was “exceeding historic high water marks of detainees to pursue their ideologically driven policy agenda.” But Merkley, a member of the powerful Senate appropriations committee, demanded ICE account for how it had somehow found the money—something it and the Department of Homeland Security would not do in response to The Daily Beast’s questions.

“It is incredibly important that ICE explain how they’re paying for nearly 4,000 more beds. In September, when I discovered that ICE had been reprogramming FEMA dollars to pay for immigrant detention centers, I wasn’t given the information from the administration. I wasn’t given the information as a member of the Senate appropriations committee. I found the information through outside resources,” Merkley said.

“The plain fact is that the administration never wanted anyone to know how they were planning to pay to execute their plan. They used a mechanism that was never intended to see the light of day,” he added.

ICE recently reported to Congress that, as of October 20, its average daily population in detention had reached 44,631 people. The figure is not classified, but it has not been made available to the public. A congressional office confirmed it to The Daily Beast.

That’s 2,500 people more than the most recent detentions statistic ICE told The Daily Beast it had: 42,105 people locked up as of September 15. By way of contrast, in October, Customs and Border patrol arrested 28,112 people, as the Washington Post first reported—far less in a month than ICE keeps imprisoned every day.

“ The rise in detentions is indicative of the fact that the Trump administration has weaponized ICE into an entity that... fits with the anti-immigrant actions of this administration. ” — Rep. Raul Grijalva

The steep rise in detentions is “indicative of the fact that the Trump administration has weaponized ICE into an entity that far exceeds the agency’s original mandate and fits with the anti-immigrant actions of this administration,” Rep. Raul Grijalva, an Arizona Democrat, told The Daily Beast. “With little accountability and oversight—and a long track record of abuse—I’m concerned that the vast majority of those in ICE custody include many innocent people who’ve done nothing wrong.”

It’s the latest milestone for detentions set during the Trump administration—which surpassed the record number of immigrants Barack Obama’s administration imprisoned. Last November, ICE’s jails held a daily average of 39,322 people. “This marks the second year in a row the U.S. government hit an unprecedented high in how many immigrants it incarcerates,” the National Immigrant Justice Center found back then, after the Immigration Legal Resource Center obtained the detentions data through Freedom of Information Act requests. Those internal records indicated that the vast majority of detainees posed no threat.

“ICE takes people from American homes and communities in early morning raids, from courtrooms and workplaces, and from the border where they arrive seeking safety and protection, and jails them thousands of miles from their lawyers and their loved ones. Inside, they suffer solitary confinement, unsafe conditions, and severe isolation,” said Heidi Altman, the National Immigration Justice Center’s policy director.

“From a moral perspective, 44,000 is an astonishing number of people to be separated from their families and communities and held within a system that DHS's own Inspector General has criticized for abusive conditions,” added the Detention Watch Network’s Mary Small.

The size of the number can obscure the experience of detention for those locked up. Several migrants, held in Texas, were separated from their children for a second time after the parents protested their jail conditions. One man held in Louisiana said ICE fed detainees food so inedible that cats wouldn’t eat it.

“ The size of the number can obscure the experience of detention. One man held in Louisiana said ICE fed detainees food so inedible that cats wouldn’t eat it. ”

A woman detained for 11 months, Floricel Liborio Ramos, wrote about immigration cells so sweltering during the summer that they rendered her plastic mattress unusable. “We used to clean the floor with our sanitary towels and then sleep on the floor because it was made of concrete, and so it was colder,” she wrote. What physical relief it provided couldn’t reduce the anxiety of being separated from her children.

ICE’s two most recent submissions to Congress justifying its budgets show a vast upward trend in its detention operations. In March, that surge prompted the congressional appropriations committees to give ICE $7.1 billion, its highest budget ever, including $4.1 billion for immigrant removal and detention operations, some $401 million over the previous year.

The extra money came with an explicit warning.

From October 1, 2017 through that March, House appropriators noted, ICE “exceeded its annualized rate of funding for Custody Operations,” according to the Congressional Record. Going forward, “ICE is directed to manage its resources in a way that ensures it will not exceed the annualized rate of funding for the fiscal year.” Congress funded an average daily detention population of 40,520 people—well below the the 51,000 beds the administration requested. (ICE prefers to count detention size in terms of “beds” rather than people.)

Democrats on the House appropriations committee noted that the funding level required “ICE to reduce the number of detention beds in use between now and the end of FY [fiscal year] 2018.”

An ICE spokesperson, Danielle Bennett, acknowledged that Congress funded ICE for 40,520 average daily detainees this year, “though ICE does have the flexibility to go above that number.” Neither Bennett nor DHS answered The Daily Beast’s repeated questions about where the money for thousands more detentions every day came from.

This summer, when ICE ran out of money for detentions, its Department of Homeland Security parent simply took money from other parts of its budget to quietly pump money into ICE detentions.

In a document revealed by Merkley to MSNBC’s Rachel Maddow in September, ICE in August informed Congress that its custody operations were running a serious deficit. “ICE must have sufficient detention bed capacity to detain illegal aliens when necessary as it enforces the Nation’s immigration laws as fairly and effectively as possible,” it stated. Using the “best available data, historical trends and modeling,” ICE said it was likely to detain 2,359 more people than its congressional funding allowed.*

DHS informed Congress that it found ICE the money from accounts held by the Federal Emergency Management Agency, the Transportation Security Administration’s aviation safety programming, the Coast Guard, and ICE’s own Homeland Security Investigations component. It wasn’t a request—it was an after-the-fact notification.

DHS says the money didn’t come out of any disaster relief or recovery fund, and that the nearly $10 million or so it took from FEMA came from administrative overhead. Merkley disputes that, and told The Daily Beast that the new detainee highs underscored ICE’s opacity.

“There is no ambiguity about how this is supposed to work,” Merkley said. “It is Congress’ job to decide budgets and ICE must work within the budget that Congress sets. Pulling money from FEMA during hurricane season to pay for the administration’s zero tolerance child-snatching agenda is unacceptable. Striping cancer research dollars to fund child prisons is unacceptable.”

“ Make no mistake, this is, at least in part, an effort to advance their plan to inflict maximum cruelty on many people who are seeking asylum in this country after fleeing danger and in their home countries. ” — Sen. Jeff Merkley

But even after DHS acknowledged pumping money into ICE’s detention budget, it wasn’t enough. In September, ICE asked Congress to give it $1 billion-with-a-B in the continuing resolution—and Congress specifically declined. But, The Daily Beast has confirmed, that same month, the detention numbers continued to swell anyway. As of September 19, the day the Senate passed a continuing resolution agencies like DHS through December, ICE had 43,714 people in its jails, a figure confirmed by a different congressional office. (ICE claimed to The Daily Beast that four days earlier, September 15, it had 1609 fewer people than that detained.)

In other words, since at least mid-September, ICE has busted through its congressionally mandated detention cap of 40,520 people by between 3,000 and 4,000 people—even after surreptitiously getting money from elsewhere in DHS.

“It’s outrageous that ICE is so dramatically overspending without explaining how they'll pay for it,” said the Detention Watch Network’s Small. “Given the agency's history of fiscal manipulations and the clear human cost, Congress should aggressively intervene to reverse this reckless expansion ahead of the December 7 deadline.”

Legislators and activists aren’t the only ones warning that ICE plays accounting games. In April, the Government Accountability Office released a report finding that for years, ICE employed dubious methodology that consistently undercounted how much its detentions actually cost. In fiscal 2016, ICE lowballed each detention bed by $5—which meant that the total detention costs estimated in its budget submission were too low by $62 million. “ICE's methods for estimating detention costs do not fully meet the four characteristics of a reliable cost estimate,” the GAO concluded.

“Ensuring there are sufficient beds available to meet the current demand for detention space is crucial to the success of ICE’s mission,” ICE spokesperson Bennett said. “Accordingly, the agency is continually reviewing its detention requirements and exploring options that will afford ICE the operational flexibility needed to house the full range of detainees in the agency’s custody.”

Bennett noted that the administration is asking in its next budget for nearly $2.8 billion in detentions funding for an average daily detentions population of 52,000—an indication that ICE intends to set even more records for immigrants behind bars.

“ICE needs to be forthcoming in the ways it shuffled money around to pay for Donald Trump’s deportation and detention agenda. One of the major issues plaguing ICE is its lack of transparency and accountability,” said Grijalva. “Congress is the branch of government charged with appropriating money and providing oversight. If DHS is using taxpayer money from another agency to pay for Donald Trump’s family separations and mass detention at the border, Congress and the American people have a right to know.”

For his part, Merkley warned that ICE’s financial shell games undermined its budget request.

“Congress should absolutely not pay a single penny more to fuel the administration’s agenda until there are clear and transparent explanations for what they’re planning on doing with the money,” he said. “Make no mistake, this is, at least in part, an effort to advance their plan to inflict maximum cruelty on many people who are seeking asylum in this country after fleeing danger and in their home countries.”