Three school buses carrying 79 middle school students on a class trip collided Friday in western Connecticut, injuring 19 children.

The seventh-grade students from Sage Park Middle School in Windsor were returning home from a trip to White Memorial Conservation Park.

Police said the chain-reaction crash occurred when the first two buses in the convoy yielded for a car, but the last bus failed to stop.

School officials said 19 students were taken to a hospital for observation after complaining of minor injuries. They were met there by their parents, the officials said.

Four adults were also treated for minor injuries, police said.

"We're fortunate there were no serious injuries," said Windsor Schools Superintendent Elizabeth Feser.

The other students were taken by different buses to a local fire station to await transportation back to Windsor. State Police spokesman Trooper William Tate said the students' parents had been notified.