The first person diagnosed with Ebola in the United States, Thomas Eric Duncan, died on Wednesday morning at a Dallas hospital, a hospital spokesman said.

"It is with profound sadness and heartfelt disappointment that we must inform you of the death of Thomas Eric Duncan this morning at 7:51 am," hospital spokesman Wendell Watson said in an emailed statement.

Duncan became ill after arriving in the Texas city from the West African country of Liberia on Sept. 20 to visit family, heightening concerns the world's worst Ebola outbreak on record could spread in the United States.