Medics took the two patients to the hospital with life-threatening injuries after they were hit by the tour bus, a fire department spokesman said.
The D.C. police major crash unit was investigating the cause of the crash. No further details were immediately available. The tour bus, which had the company name Eyre Bus, Tour, Travel on the side, was parked in the 700 block of Pennsylvania Avenue near the Navy Memorial and across the street from the National Archives.
No further information was immediately released.