OMAHA, Neb. (AP) — A doctor who became infected with Ebola while working in Liberia has arrived at a Nebraska hospital for treatment.

Dr. Rick Sacra was driven by ambulance to the Nebraska Medical Center in Omaha after landing a little after 6 a.m. Friday at Offutt Air Force Base just south of Omaha. His ambulance went into a hospital receiving bay and vanished from public view at 6:38 a.m. He will begin treatment in the hospital's 10-bed special isolation unit, the largest of four such units in the U.S.

Sacra, from the Boston area, went to Liberia even after hearing that two American missionaries had become infected. He served with the North Carolina-based charity SIM. Sacra didn't treat Ebola patients but delivered babies, so it's unclear how he got infected.

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