ICE accidentally leaked personal info of more than 6,000 immigrants who applied for protections.
Many of the immigrants were from Iran, Russia, and China fleeing persecution, according to LA Times.
The agency said the leak, which they said was "unintentional," was left up for five hours.
More than 6,000 immigrants, including many who fled persecution to come to the US, had critical personal information accidentally shared in an Immigration and Customs Enforcement data leak earlier this week.
Human rights organization Human Rights First notified the agency of the massive leak on Monday, the Los Angeles Times reported. The list of 6,252 immigrants, which included their case status and names, was publicly posted on the website for five hours, according to ICE.
The excel sheet containing sensitive information about migrants seeking protection in the US was mistakenly published during an update to the immigration agency's website. The list included people from Iran, Russia, and China who have applied for immigration protections from persecution and torture, according to the LA Times.
"Upon notification, US Immigration and Customs Enforcement took swift action to immediately rectify the error," an ICE spokesperson said in a statement to Insider. "Though unintentional, this release of information is a breach of policy and the agency is investigating the incident and taking all corrective actions necessary. ICE is notifying noncitizens impacted by the disclosure."
The agency said the spreadsheet was mistakenly uploaded at 9:45 a.m. ET. By 1:53 p.m., Human Rights First had notified ICE about the leak. ICE said in a statement that the list was removed 10 minutes later.
Immigration advocates said the leak created grave security risks for the migrants, even if the data was deleted.
"ICE cannot be trusted with people's data," Oliver Merino, a coordinator for the Immigrant Legal Resource Center, told Insider. "Here's another example of ICE's complete disregard for peoples safety and well-being."
He added: "The consequences of this so-called 'mistake' could impact peoples lives and another reason why they should not be deported to a place where they might face violence. "
ICE said in a statement that it is monitoring the internet for any reposting of the data and asking individuals who downloaded it to delete the content. The agency added that it is opening an internal investigation and notifying the individuals and attorneys of the leak "to determine whether the disclosure may impact the merits of their protection claim."