The deported immigrants had “infectious diseases” and they went by buses through the Egyptian border, said the department.
On Monday the department deported more than 100 illegal immigrants to Nigeria and Egypt.
The International Organization for Migration said Sunday that there are more than 650,000 illegal immigrants in Libya, of whom about 6,000, including women and children, are being held in detention centers.
Thousands of illegal immigrants, mostly Africans, chose to cross the Mediterranean Sea towards Europe from Libya as the country has been mired in insecurity and chaos ever since the fall of its former leader Muammar Gaddafi in 2011.
Shelters in Libya are crowded with thousands of migrants rescued at sea or arrested by the Libyan security services despite international calls to close those centers.