The hospital said the patient appears to be an African American man in his mid-30s to late-40s. He's 6'2" and 180 pounds with brown eyes, a beard and a healed midline chest scar.
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Memorial Hermann released a photo of the patient lying in a hospital bed.
A hospital representative said the patient was found unconscious and picked up by Houston fire officials, who brought him to the hospital with no belongings.
Officials did not specifically say where the man was located.
Anyone who has knowledge of the patient is encouraged to contact Memorial Hermann-Texas Medical Center at 713-704-6721.