The accident happened shortly after 3 p.m. at the intersection of South Simms Street and West Brandt Place.
At least one victim was taken to Children's Hospital. Her condition has not been confirmed. State Patrol says the others were taken to St. Anthony Hospital in Lakewood with non life-threatening injuries.
The mother of one of those girls, who asked us not to use her name, told us by phone her daughter may have to stay at the hospital overnight but all three girls are expected to be OK.
Tammy Basile was at the stop light in her car and witnessed the accident. From her vantage point, the teenage girls did everything right.
"It's a busy intersection. They looked both ways, they crossed," Basile said.
CSP investigators returned to the scene just after 5:30 p.m. to recreate the accident.
"When the bus was turning, I said to myself, 'He's getting awful close to those girls. Is he going to stop?' And then he didn't," Basile said.
The Jeffco Schools bus hit the three girls, who have been identified as Summit Ridge Middle School students, just after classes let out for the day.
According to investigators and witness accounts, the bus was turning South onto Simms around 3:09 p.m. when it hit the girls on the crosswalk as they headed east.
"She was kind of in shock. And I said, 'Please lay down, you cannot move.' She was bleeding. And she goes, 'I don't know what happened.' And I said, 'You were just hit by a school bus,'" Basile said.
Jeffco Schools District spokesperson Lynn Setzer says the bus driver is a substitute and was hired in October 2011.
"We're just devastated by this. We're devastated for the students that were injured and for their families. We're hoping and praying that they make a full recovery, a quick recovery. Our bus drivers take this so seriously. They try their very best to keep the students safe so something like this absolutely devastates them." Setzer said.
Setzer says the bus driver received the standard 98 hours of training, which is required for a substitute.
"Substitutes generally drive a different route every day. So, I don't know how familiar he was with this," Setzer said.
CSP says the bus driver was not under the influence of alcohol or drugs and has not been cited for this accident.
He is on paid leave, which is standard procedure, as the investigation continues.
Basile says her thoughts are with the girls who were hit.
"I have a 10-year-old son, so it was really tough for me to see. I just hope they're all OK. My prayers go out to them and their families," Basile said.
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