UPDATED 05/17/11 1:05 p.m.

EVANSTON, Ill. (CBS) — Two school buses were involved in an accident late Tuesday morning in the heart of downtown Evanston, sending 21 people to area hospitals.

Newsradio 780’s Bob Roberts reports the school buses crashed at Davis Street and Chicago Avenue.

Just after 11 a.m., the two school buses were headed north in the 1500 block of Chicago Avenue in Evanston, near Davis Street, when one rear-ended the other while in traffic.

LISTEN: Newsradio 780’s Bob Roberts Reports

The students from both buses are from Rowe Elementary Charter School, at 1454 W. Superior St. in the West Town neighborhood, and were taking a field trip to Northwestern University, Evanston police said.

One bus had 24 people aboard, the other 26. In total, 21 people – one adult and 20 children, were taken to area hospitals.

All the accident victims had non-life-threatening injuries, mostly suffering from neck and back pain, police said.

Chopper 2 captured one of the buses being removed by a tow truck–but it didn’t appear to have sustained major damage. Young children carrying lunch bags were being escorted down Chicago Avenue, but none of them appeared to be injured.

Evanston Police Cmdr. Tom Guenther said that the buses were one behind the other at the stop light at Chicago Avenue and Davis Street,heading northbound on Chicago. When the light turned green, the first bus began to move, but had to stop short because of traffic in front of him.

The driver of the second bus allegedly told police he was looking in his mirror and did not see the bus ahead. Evanston Fire Chief Greg Klaiber said the second bus rear-ended the first “with fairly high impact.”

Ambulances from Evanston, Wilmette, Winnetka, Skokie, Glenview, Lincolnwood, Glencoe, Northfield and Niles took turns picking up the injured students and adult, taking them to a hospital, and then returning in case there were more to be transported.

Parents, teachers and Rowe’s principal were on board the buses. They oversaw the students who escaped injury and then led them on foot to the Northwestern campus for the field trip.

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