A toll-free hotline designed to help immigrants in detention centers get legal counsel was shut down by Immigration and Customs Enforcement after the number was mentioned in the acclaimed Netflix series "Orange Is The New Black," according to the California-based group that runs it.

The Freedom for Immigrants’ National Immigration Detention Hotline has been an available resource to people in immigration detention since 2013, but it was shut down on Aug. 7, about two weeks after the premiere of the last season of "Orange Is The New Black," the organization said in a press release.

The hotline was featured in various episodes. After two longtime characters, "Blanca" and "Maritza," end up in deportation proceedings, they learn that immigrants don’t have the right to a free phone call after they are detained. Without access to money, both characters learn about the Freedom for Immigrants hotline and start passing out the number to others in the facility.

“The timing of the shutdown is deeply concerning. Freedom for Immigrants is being targeted for exposing abuses in detention and amplifying the stories of people suffering in the system” said Christina Fialho, an attorney and executive director of Freedom for Immigrants, in a statement.

Seven producers and actors of the popular Netflix show joined 121 organizations, such as the American Civil Liberties Union and the Southern Poverty Law Center, in signing a letter sent to ICE on Thursday.

“We are heartbroken to hear about the shutdown of this hotline," said Vicci Martinez, who plays "Daddy" in "Orange Is The New Black" and one of the actors who signed the letter. "We stand with Freedom for Immigrants and urge ICE to restore their hotline immediately.”

The letter was sent to ICE alongside a cease and desist notice "for blocking Freedom for Immigrants’ ICE Pro Bono telephone extension from being accessed nationwide."

Actresses Diane Guerrero and Laura Gómez, who played "Maritza" and "Blanca" respectively, were part of the "Orange Is The New Black" cast who signed the letter to ICE.

Cynthia Galaz, the director of the organization's national hotline, said the service "allows for communication and community building between those inside and outside of detention."

"By blocking access to Freedom for Immigrants’ hotline, ICE furthers community disenfranchisement and prevents the public from knowing about what happens inside these facilities,” she added.

A formerly detained immigrant and frequent hotline caller who identifies by a first name, Vlentín, said in a statement that after being detained in Louisiana and California, "having access to the hotline was very important" because it "was my only connection to the outside to report the medical neglect I suffered."

"I also made friends with many volunteers, who came to recognize me as soon as I said, 'Hello.' The hotline was crucial for me in the face of the abuse and solitude I endured while in detention,” Vlentín, who is also an activist, added.

An ICE official told NBC News in a statement that "all ICE facilities provide detainees with reasonable and equitable access to telephones."

Detainees are allowed to "make free calls to an ICE-approved list of free legal service providers for the purpose of obtaining initial legal representation," but three-way calling and call forwarding are "strictly prohibited," ICE said.

While the agency did not specifically comment on the termination of Freedom for Immigrants' hotline, an ICE official said that pro bono organizations found to be violating their telephone rules "may be removed from the platform."

"However, removal from this platform in no way limits the ability of an ICE detainee to phone such an organization directly should the detainee wish to do so," the agency added.

Follow NBC Latino on Facebook, Twitter and Instagram.