VANCOUVER - The company that owns the tour bus involved in Sunday's fatal bus crash in Oregon has posted a letter on the door of its Vancouver office, saying employees are grieving with the victims' families and assisting the survivors.

Mi Joo Tour & Travel has otherwise refused to comment on the accident as Oregon police slowly identify the dead publicly, including 11-year-old Youmin Kim, a South Korean girl who was staying with a B.C. family.

The girl and 75-year-old Yongho Lee, a resident of Lynwood, Wash., became the fourth and fifth victims named by police.

Nine people died and 38 were injured when the tour bus travelling westbound in the left lane of Interstate 84, hit a concrete barrier, veered across both westbound lanes and went through the guardrail, plunging about 60 metres down an embankment.

"On behalf of Mi Joo Tour, we share in the tremendous grief experienced by all of the survivors and families of the people involved in this terrible tragedy," stated the note posted on the company's door.

"We are focused on assisting and supporting the survivors and families. No further comment at this time."

According to a business licence, Mi Joo Tour & Travel is owned by an Ik-Kyu or Edward Kang, but calls to a home listed under that name were not returned.

Oregon police also announced Wednesday the state's medical examiner's office has positively identified another victim, but won't release that name until Thursday, giving authorities more time to notify next of kin.

Also killed in the crash were Dale William Osborn, 57, of Spanaway, Wash., and Oun Hong Jung, 67, and his wife Joong Wha Kim, 63, who were staying with relatives in Washington state.

Lt. Gregg Hastings said in an email to The Canadian Press that the Oregon State Police interviewed the 54-year-old driver of the bus before he was released from hospital but he declined to answer further questions.

On Wednesday afternoon, several survivors of the crash were being driven back to B.C.

Police said they expect the investigation to take at least one month before the file is handed over to prosecutors who will consider any further action.

Investigators with the state police and the National Transportation Safety Board inspected the bus Tuesday and conducted a detailed inventory of personal gear and documents.

The bus was carrying tourists, including some who had been living in Canada, and was on the final leg of a nine-day tour of the western United States.

I-84 is a major east-west highway through Oregon that follows the Columbia River Gorge.