An undocumented immigrant shielded from deportation and granted work authorization under an Obama-implemented program has been detained in Seattle, due to what the government says is his gang affiliation.

According to Reuters, Daniel Ramirez Medina was brought to the United States as a child and granted quasi-legal status under the Deferred Action for Childhood Arrivals (DACA) program. The previous administration created DACA to allow undocumented immigrants brought to the United States as children — or “Dreamers” — to remain in the country.

Immigration officials apprehended and detained Ramirez on Friday. One of the attorney’s representing Ramirez — Ethan Dettmer, a partner at Gibson Dunn & Crutcher — told Reuters that his client is likely the first DACA recipient detained under the Trump administration.

“We are hoping this detention was a mistake,” Dettmer said.

According to immigration officials, however, Ramirez was apprehended due to his gang ties.

“ICE officers took Mr Ramirez into custody based on his admitted gang affiliation and risk to public safety,” Immigration and Customs Enforcement (ICE) spokeswoman, Rose Richeson, said in a statement to Reuters.

Ramirez denies that he is part of a gang.

“While in custody, he was repeatedly pressured by U.S. Immigration and Customs Enforcement agents to falsely admit affiliation,” Dettmer said to Reuters, calling the ICE statement “not accurate.”

Gang member or not, Ramirez’s arrest has immigration activists concerned and heated.

“Daniel must be given his freedom, now. Donald Trump’s executive orders have made everyone a priority for deportation. Under Trump’s America, no one is safe. Donald Trump and Republicans must say in no uncertain terms that DACA recipients are safe,” Greisa Martinez, the advocacy director of the pro-amnesty group United We Dream, said in a statement.

There are currently about 750,000 undocumented immigrants covered by DACA in the United States.

Trump promised a crackdown on illegal immigration during the presidential campaign but, last month, indicated he was open to offering leeway to Dreamers.

“They are here illegally. They shouldn’t be very worried,” he said during an interview with ABC News. “I do have a big heart. We’re going to take care of everybody. We’re going to have a very strong border. We’re gonna have a very solid border. Where you have great people that are here that have done a good job, they should be far less worried.”

After Ramirez’s arrest, the National Council of La Raza, a Latino advocacy group, chastised the administration for not granting “Dreamers” protection.

Reuters reports that Ramirez and his lawyers are disputing his detention in Seattle federal court.