SAN FRANCISCO - Five people were killed and at least 20 more injured Sunday morning when a tour bus lost control and crashed on the icy road in the US state of Oregon.

Oregon State Police said the bus lost control at around 10:30 am local time and crashed down an embankment on an ice-covered Interstate 84 east of Pendleton, a city about 336 km east to Portland, the most populous city in Oregon.

The police said there were around 50 passengers on the bus, but did not release further details, according to local newspaper East Oregonian.

Pendleton fire department officials told the newspaper that crews freed the last "viable victims" from the crash and a local hospital received about 20 injured passengers by 1 pm local time.

Local authorities have closed part of the highway and urged drivers to go slow due to road conditions.