U.S. Customs and Border Protection acknowledged Monday that it is exploring additional locations to house the thousands of illegal immigrants who continue to flood across the southwestern U.S. border, and that it may need this expanded capacity for some time to deal with the crisis.

CBP, which is housed in the Department of Homeland Security, said over the weekend that it has opened a “temporary holding facility” for immigrants in Tornillo, Texas. That announcement said the plan is to keep that facility, which can hold 500 people, for 30 days, “pending any changes in the volume of people arriving at the ports or crossing the border.”