(The Hill) — Sen. Ed Markey (D-Mass.) sent a letter Tuesday to the Department of Homeland Security (DHS) urging it to discontinue the use of a smartphone app required by migrants seeking asylum at the southern border to use.

The CBP One app, which was rolled out in 2021, was established to allow migrants to submit applications for asylum before they cross the U.S. border. Markey said in his letter that requiring migrants to submit sensitive information, including biometric and location data, on the app raises “serious privacy concerns,” and demanded that the DHS cease its use of it.

“This expanded use of the CBP One app raises troubling issues of inequitable access to — and impermissible limits on — asylum, and has been plagued by significant technical problems and privacy concerns. DHS should shelve the CBP One app immediately,” Markey said in his letter. 

“Rather than mandating use of an app that is inaccessible to many migrants, and violates both their privacy and international law, DHS should instead implement a compassionate, lawful, and human rights centered approach for those seeking asylum in the United States,” he continued.

He said that the use of this technology has also faced technical problems, including with its facial recognition software misidentifying people of color.

“Technology can facilitate asylum processing, but we cannot allow it to create a tiered system that treats asylum seekers differently based on their economic status — including the ability to pay for travel — language, nationality, or race,” he said.

The app has negative ratings on both the Google Play and Apple app stores, with many users criticizing the app for crashing and other technical issues.

When the rollout of CBP One was announced in 2021, Customs and Border Protection (CBP) said the app was meant to “streamline” legal travel to the United States.

“As part of CBP’s comprehensive effort to improve the security of our nation’s borders while enhancing legitimate travel and trade, CBP One will provide increased accessibility and transparency to some of CBP’s most utilized services,” the CBP website states.

This letter comes as the Biden administration reportedly plans to adopt a new rule that would prohibit migrants from seeking asylum in the United States if they did not initially attempt to apply for it from the country they were coming from. Migrants would not be eligible for the program if they cross an international border without applying first.

President Biden has warned migrants seeking asylum to “not just show up at the border,” saying that they should stay where they are to apply for a newly announced parole program, or they will not qualify. He announced last month that the parole program will be expanded for migrants from Venezuela, Nicaragua and Haiti.