There are nearly one million illegal immigrants in the US who have ignored official deportation orders because US law enforcement is at an all-time low, new figures have shown.

The one million illegals also include at least 170,000 convicted criminals.

According to a report by the Center for Immigration Studies, only a “small fraction” of the illegals are even being detained by Immigration and Customs Enforcement (ICE), meaning “most of them remain free on the streets, where they can commit crimes and continue living in the shadows.”

“The fact that almost 10 percent of the illegal resident population has already been ordered removed and is still here illustrates just how dysfunctional our immigration enforcement system is,” the report said.

“It also should be of great concern that 20 percent of them are conviction criminals, and that most of these are at large in our communities,” study author Jessica Vaughan said.

About 60 percent of the aliens come from just four countries: Mexico, El Salvador, Honduras, and Guatemala, and a disproportionate number of the non-departed criminal aliens are citizens of Cuba.

About 20 percent of the “non-departed aliens” have at least one criminal conviction. Nearly all of these individuals — and nearly all of the convicted criminals — are at large, not in ICE custody.

Ms. Vaughan said the 925,193 aliens who were still here despite a deportation order break down into three categories.

In some cases their home countries refuse to take them back, and US officials feel constrained by law to release them; other times they are released by sanctuary cities, who help thwart deportations; and still others abscond on their own.

Mexicans account for the most aliens, with nearly 200,000 ignoring deportation orders. About a third of those are convicted criminals.

El Salvador accounts for more than 150,000 of the aliens, and 10,000 of them are convicted criminals.

Perhaps most troubling is that the population is steadily growing, with the Obama administration tracking down fewer than 10,000 fugitives a year on the streets.

Even when criminals detected by checking local prisons and jails are included, the number of those deported from the interior of the US is far less than 100,000.

But some 179,040 new criminal aliens were given final orders or removal in 2015 yet remained in the country, Ms. Vaughan said, citing data obtained by the Senate Judiciary Committee.

The top countries of citizenship of “non-departed aliens” were, according to these figures, as follows:

Mexico 187,384; El Salvador 159,509; Honduras 120,118; Guatemala 99,201; China 38,778; Cuba 35,156; Haiti 30,804; and Brazil 25,703.