MADRAS, Ore. -- Three people died and multiple people were injured after a car that was hit from behind was pushed into the eastbound lane and collided with a van on Highway 26 on Monday evening.

Highway 26 was closed for almost six hours between mileposts 71 and 96 while the investigation was completed. The crash, near milepost 86 on the Warm Springs Indian Reservation, was first reported at about 4 p.m.

The three people who died were identified Tuesday morning by Oregon State Police as 37-year-old Adam Clausen and 39-year-old Shannon O'Leary of Portland, and 34-year-old Robert Burke of Reno, Nevada.

O'Leary was an assistant professor of physics at Lewis & Clark College in Portland. She joined the faculty in 2011, according to the college website.

A crowd funding campaign has been set up to help provide for the 4-year-old son she and Clausen left behind. He was with them at the time of the crash but was not injured, according to the GoFundMe page.

Rachel Burke, 29, of Reno, Nevada, was taken by air ambulance to a hospital in Bend with serious injuries.

Several other travelers involved in the crash were taken to hospitals with minor injuries, including 31-year-old Nathan Verhaeghe, of Spokane, Washington. A 4-year-old child and a 22-month-old child were also transported to area hospitals with minor injuries.

Police say Clausen's car was pushed into the eastbound lane after it was hit from behind by Verhaeghe's car. A van, driven by Burke, then hit Clausen's car.

Officials said speed and other contributing factors are being investigated as causes of the crash.