The accident caused the death of seven people: Six were Chinese nationals, including one from the Hong Kong Special Administrative Region, and the seventh was a Chinese tour guide with a US passport, a spokesman with the administration said, quoting the list provided by the Chinese Consulate General in Los Angeles.

Eight other Chinese nationals were injured when the tour bus crashed just south of the Hoover Dam following a visit to the Grand Canyon, an optional trip not included in the basic tour package. Five members of the group skipped the trip.

The collision occurred when the group's bus veered to the right of the northbound lanes of Highway 93, overcorrected, and darted across the desert median before hitting oncoming traffic, according to the Las Vegas Review-Journal.

Shanghai has set up a task force headed by Vice-Mayor Zhao Wen to handle the investigation into the accident, in collaboration with the Consulate General in Los Angeles.

"The passports will be issued Tuesday and the airline has reserved seats for them," Cheng said.

The China Pacific Insurance (Group) Co Ltd (CPIC) has paid 1.85 million yuan ($270,000) to families of the six dead from the mainland and Hong Kong, according to the CPIC Shanghai Branch.

Xinhua contributed to the story