LATEST: The Strip was reopened to traffic around 6 p.m.
All three people taken to the hospital are expected to survive.
Witnesses say several people went over to help, before paramedics arrived.
They said when the cab driver was pulled from the car he appeared to be alert and talking to first responders.
"He was talking, giving thumbs up and stuff," Lori Creek said. "He seemed to be okay."
Police say they plan to use surveillance cameras in the area to determine who was at fault in the accident.
UPDATE: Chopper 13 shows that the crash involved a taxicab. The driver was alone in the cab and was taken to hospital in critical condition.
There were at least 3 people in a red car that collided with the taxi. One person was observed being taken by ambulance. The extent of other injuries is unknown at this time.
There was a third vehicle involved and the driver left the scene after talking to police.
LAS VEGAS, NV (KTNV) -- Police are on the scene of a serious crash on the Las Vegas Strip.
It was reported at 2:48 p.m. Wednesday. The crash happened in the southbound lanes of Las Vegas Boulevard in front of Caesars Palace.
Investigators are reporting this to be a critical-injury crash with multiple vehicles involved.
Northbound traffic is stopped at Flamingo Road and southbound traffic is stopped at Caesars Palace.
Action News will post updates as they become available.