CHICAGO (AP) — More than 10,000 Illinois residents who bought insurance through President Barack Obama’s health care law could have their coverage canceled if they don’t send citizenship and immigration documents to confirm their eligibility by Sept. 5.

Federal officials say they’re sending letters to approximately 10,300 Illinois consumers asking for their paperwork. The letters caution that coverage will end by Sept. 30 without the documentation. The letters were sent in English and in Spanish.