On Saturday, March 3, 2018, at about 6:20 p.m., Oregon State Police Troopers and emergency personnel responded to the report of a multiple vehicle collision on Interstate 84 at milepost 223 westbound. A total of 20 vehicles were involved. (Seven commercial motor vehicles and 13 passenger vehicles). The preliminary investigation revealed speed and black ice were contributing factors creating a domino effect resulting in the multiple vehicle collisions. Injured persons were transported by Life Flight and ambulance to St. Anthony’s Hospital in Pendleton and Kadlec Regional Medical Center, in Richland, WA. OSP was assisted by Pendleton Fire, Umatilla County Fire District 1, Life Flight, Medic 400-Athena, Umatilla County Sheriff’s Office, Umatilla County Search and Rescue, Umatilla County Emergency Management, Umatilla Tribal Fire Department, Umatilla Tribal Police Department, Oregon Department of Transportation (ODOT). ODOT closed Interstate 84 westbound lanes until it was reopened at 8:00 a.m., on March 4, 2018.  Update:  Investigators estimate that nine occupants of the collisions were transported to area hospitals for treatment and five of those were in serious condition. Because of the complexity of the investigation, no names will be released at this time.