Firefighters responded to a roof fire at the Bellagio in Las Vegas Thursday night.
A second alarm was called while they battled the flames.
The fire has been knocked down and put out, according to the Clark County Fire Department.
Crews had a problem gaining access to it, and no cause is determined.
The department said the building saw exterior damage.
Ten engines, four truck companies, six rescues, four battalion chiefs, one deputy chief and two air rescue units, totaling 77 personnel responded.
Las Vegas Boulevard was closed.
The fire department was called at 10:46 p.m. and crews arrived at 10:50 p.m. The fire was knocked down at 11:09 p.m.
"Firefighting efforts were extremely difficult due to the location of the fire and access to the location," assistant fire chief Larry Haydu said.