Four detainees have escaped from a federal immigration detention center in Newark, New Jersey, amid reports of disorder breaking out there, according to the Department of Homeland Security.

More “law enforcement partners” have been brought in to find the detainees missing from Delaney Hall, according to an emailed statement attributed to a senior DHS official whom the department did not identify. The statement also didn’t specify which law enforcement agencies are involved. The identifies of the people who escaped are unknown.