As police officers pleaded for all available medics to converge on the scene of the Colorado movie theater massacre last week, a two-man ambulance crew and their rig were idling just a few miles away.

While some ambulances were quickly called to duty, it took dispatchers more than 20 minutes into the crisis to ask the Cunningham Fire Protection District and other nearby agencies to provide aid at the multiplex in the Denver suburb of Aurora.

By the time the Cunningham crew arrived, it was more than a half hour after authorities got first word that a gunman opened fire at a packed midnight showing of "The Dark Knight Rises," killing 12 people and injuring dozens of others.

About nine minutes in, one officer in an urgent voice declared bluntly: "I need as many ambulances as we can." Four had been dispatched at that time, according to one person on the scanner traffic.

An officer said he was going to take a victim in his car.

Eleven minutes in, a first responder again barks: "Dispatch, get me some ambulances!" A coordinator replied that Rural/Metro – the private ambulance provider for the area that also declined comment on the response – was sending all available units in Aurora.

The Cunningham unit, however, had not been called and sat idle for 10 more minutes. The department operates separately from Aurora officials but coordinates with them on a near-daily basi