When Nak Kim “Rickie” Chhoeun arrived at the Immigration and Customs Enforcement (Ice) field office in Los Angeles last October, he thought it would be a routine check-in.

Instead, he was arrested and detained for six months, unsure whether he would ever see his family, friends or apartment again.

Chhoeun, 43, is one of the nearly 12 million people in the US who are looking over their shoulders for Ice, the interior enforcement immigration agency emboldened by Donald Trump to round up every undocumented immigrant.

Ice agents show up announced at workplaces, doorsteps and courthouses, ready to arrest anyone without legal papers and send them through the agency’s detention centers and back to the country they came from.

A year after his arrest, Chhoeun has now learned routine check-ins are a thing of the past and under Trump life is dramatically different for the millions of other undocumented people, just like him, who have spent decades building lives in the US.

‘Any minute they could come and pick me up and deport me,’ says Nak Kim ‘Rickie’ Chhoeun, who came to live in the US as a Cambodian refugee in 1981. Photograph: supplied

“I’m actually living like I’m still locked up because any minute they could come and pick me up and deport me,” Chhoeun, a 43-year-old who came to the US as a Cambodian refugee in 1981, told the Guardian. “Everything I have now is just temporary.”

Five days after taking office, Trump signed an executive order that effectively stopped Ice from prioritizing criminals for deportation. Instead, they are now going after all the estimated 11.3 million undocumented immigrants in the US at once – drawing little distinction between hardened criminals and productive community members who have started businesses, bought homes and paid their taxes.

This includes a 10-year-old with cerebral palsy Ice arrested in October 2017 after she left a Texas hospital for treatment; undocumented adults who volunteer to take custody of children who crossed the border by themselves; and an elderly couple visiting their pregnant daughter-in-law and her husband at a military base in New York for the Fourth of July holiday.

“The idea is to try to send the message to communities that everybody is at risk of deportation by arresting all sorts of people who are no kind of threat and who very well may be productive members of their communities with US citizen family members and people who rely on them and all that sort of thing,” said Omar Jadwat, director of the ACLU’s Immigrants’ Rights Project. “None of that matters to the administration is very much the message they very much want to send.”

Lawyers and advocates said this “papers, please” mentality has led to Ice targeting more people at sensitive locations such as schools and hospitals, more vulnerable populations and more people eligible for immigration relief. The same month Chhoeun was arrested, Ice deported a Detroit father who had helped police while his application for a special visa was pending.

“If you’re just looking to get your deportation numbers up and to send that message of general fear they are an attractive target for this administration,” Jadwat said.

From January to October 2017, Ice arrested 37,670 people who had no criminal convictions, according to the Transactional Records Access Clearinghouse (Trac) a non-profit, non-partisan data center at Syracuse University. That’s a 125% increase from the year before, when Ice arrested 16,673 people with no criminal convictions, according to Trac data published last month.

That jump is what has alarmed immigrant communities most, because it represents people picked up in a variety of scenarios, including outside courthouses, in workplace raids and at their homes.

And as of 30 June 2018, 58% of the 44,435 people in Ice custody had no criminal record, according to Trac. Four out of five either had no criminal record or only had a minor offense on their record such as a traffic violation.

The increase in non-criminal arrests has not gone unnoticed by the American public. Indeed it has thrust Ice into the national debate over immigration; the agency is now feared, dreaded and hated by some, and lionized and exulted by others.

San Antonio-based consultant Alonzo Peña was Ice’s deputy director from 2008 to 2010 and worked in the agency and one of its precursors, the US Customs Service, since 1984. He said until Trump took office, Ice was the “red-headed stepchild” of DHS and went largely unnoticed outside the immigration community.

Now, it regularly receives praise from Trump and attacks from the left, where an “abolish Ice” movement has emerged.

Ice was designated in 2003 under the homeland security department formed in response to 9/11. It succeeded the Immigration and Naturalization Service (INS), an agency whose tasks were divided among three other immigration agencies including Ice, which took up the investigation and enforcement role.

Where Customs and Border Patrol is focused on border apprehensions, Ice is focused on interior enforcement and has the authority to investigate anything that crosses the border including drugs, money, weapons and people.

Peña said it was “absolutely not” a realistic goal for Ice to deport all undocumented immigrants in the US and that the country needs comprehensive immigration reform to address the problems Trump claims to be resolving.

“Why would you take that budget that’s limited and not use it to say we’re going to go after the worst people who are illegal and here? … The target goal is 12 million people who are here illegally, why are you going to target a little girl with cerebral palsy?”

Peña said many, if not most, of the 20,000 Ice employees oppose some of Trump’s immigration policies, such as family separation, and question how trying to deport everyone will meet national security goals. He said they continue, however, because it’s easier to look away when you’re getting attention.

“It’s the bitter pill they’ll swallow,” Peña said. “They’ll say, ‘Hey, we know that, but we’re getting attention, we’re getting resources. If it makes him happy, we’ll do it and find another way to do the cases we still want to do.’”

Ice’s higher profile and more aggressive arrests have made the agency a target for lawyers nationwide.

In June, Ice arrested Pablo Villavicencio, a pizza delivery man in New York City, when he arrived with a bulk lunch order at Fort Hamilton army base. The father of two, who had applied for a green card before arrest, was fast-tracked for deportation but the government dropped the case last week after it received international media attention.

Luciana Villavicencio holds up a picture of her father, Pablo Villavicencio, who was detained by Ice in June as he was delivering pizza to Fort Hamilton army base. Photograph: Justin Lane/EPA

“What they would like to do is deport people and skip the whole legal process, right?” said the ACLU’s Jadwat. “That was the idea initially behind this and I think their legal position is still they can sweep these people up and put them on a plane and they’re gone before you know it. It’s only because we and other lawyers have stepped up and said you have to provide some due process before you ship someone to a place where their lives could be in danger that they haven’t been able to kind of send people abroad immediately.”

Chhoeun has been able to stay in the US because of a lawsuit filed by the Asian Law Caucus, Asian Americans Advancing Justice – Los Angeles (AAJC) and Sidley Austin LLP, on behalf of 1,900 Cambodian refugees subject to final orders of removal.

The ongoing lawsuit, which he is a lead plaintiff in, said these refugees were rounded up last autumn because of deportation orders they received decades ago for criminal convictions. Cambodia refused to accept the individuals and because they could not be detained indefinitely by Ice, they were released.

Then, in October 2017, they started to be arrested again. “The recent raids appear to be a tactic by Ice to coerce Cambodia into cooperating with a US deportation policy that breaks families apart,” AAJC explained in a statement.

Like Chhoeun, most of the class members moved to the US decades ago seeking refuge from the Khmer Rouge, whose rule left a quarter of Cambodia’s population dead from starvation, disease or execution. Chhoeun was born in 1975, the year Pol Pot’s communist “utopia” experiment began its murderous four-year reign over Cambodia.

Chhoeun said he does not have strong ties to the country. Before coming to the US at age six, he mostly lived in a Thai refugee camp. His mother, three brothers and three sisters are US citizens.

Chhoeun pleaded guilty in 1999 to charges of simple assault and illegal firearm possession. He was arrested again in October 2017 after being summoned to the Ice field office.

His neighbors thought he was dead while he was detained because his kitchen stank with rotting food. He said he can’t buy a new television, car or house because he doesn’t want to spend the money if he could be whisked away at any moment while his lawsuit plods on.

“It’s hard to live like that,” Chhoeun said. “I live in fear.”