A group of 36 lawmakers says the Department of Homeland Security (DHS) has created “disappearances” on US soil, due to the “increasingly unreliable” online system used to track people detained by immigration authorities, according to a letter shared with the Guardian.

The lawmakers, led by Senator Elizabeth Warren, are urging that the DHS inspector general’s office open an investigation into the Immigration and Customs Enforcement (ICE) “online detainee locator system” (ODLS), which has been used for years by family members, attorneys and journalists to track people in the federal immigration detention system.

“Since January 2025, that system has grown increasingly unreliable,” the lawmakers, including Senator Ben Ray Luján and House representatives Veronica Escobar and Lauren Underwood, say in the letter. “Without a functional locator system, DHS is effectively creating ‘disappearances’ on US soil, and we urge the DHS office of inspector general (OIG) to investigate this matter.”