It was the school's police resource officer and 4 Broward County deputies who failed to enter the school building during the shooting.

The following article that has an embedded video helps to clarify that a large number of Coral Gables police officers did respond to the shooting, once the camera delay had elapsed, and 40 of them did enter the building and were able to carry victims to safety and medical help.

130 Coral Springs police officers responded to school shooting, chief says
Chief Tony Pustizzi says there was tape delay while reviewing security footage

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