More than six-dozen of the animals escaped through an open gate at G-and-C Packing about 8:30 Tuesday morning.
Nearly 42 bison escaped and some hit the streets in search of a reprieve from the slaughterhouse.
Colorado Springs police tried to round up the animals.
Three were shot and killed, including one that ended up in the vicinity of a middle school. Police had notified officials with School District Eleven to keep kids inside as a precaution.
No one was hurt.
Packing house workers had advised residents not to try to apprehend the fugitives on their own.