NORTH LAS VEGAS, Nev. (AP) _ A pickup truck blew a tire and crossed a median, hitting a bus carrying Japanese tourists, authorities said. The truck driver was killed and 13 people were injured.

After the collision, the van-type bus hit two other vehicles before crashing into a fence on Interstate 15 about 10 miles north of the Las Vegas Strip.

``We're still piecing it together,'' Nevada Highway Patrol trooper Jim Olschlager said. ``But the preliminary investigation revealed the right rear tire had a partial tread separation.''

The bus driver, a 53-year-old Japanese national, and a 37-year-old Las Vegas woman in another vehicle were in fair condition with injuries that were not life-threatening, said Rick Plummer, spokesman for University Medical Center in Las Vegas.

The woman is seven months pregnant and her unborn child appeared healthy, he said.

The others injured were passengers on the tour bus. They were treated for their injuries and released within hours.

Masaya Sagawa, information officer for the Japanese consulate in San Francisco, said the tourists were from various cities in Japan.

Sagawa said he believed the group was headed to the north rim of the Grand Canyon in Arizona or to Monument Valley in Arizona and Utah.

The wreck was the second tour bus crash in two days in the Southwest.

On Thursday, a bus collided with a van pulling a trailer on the main highway to the South Rim of the Grand Canyon. Forty-eight people were injured, including three who remained in critical condition Friday at a Flagstaff, Ariz., hospital.