(Lauren Evans) A probe by the DOI found that human error, not the city's new 911 system, to be the culprit behind the four-minute delay in responding to a car crash that ultimately killed 4-year-old Ariel Russoin June.

The 42-page report maps the exact events that occurred between the moment that Russo and her grandmother were struck by an unlicensed driver and the time the first dispatched ambulance arrived at the Upper West Side scene.

The investigation arrived at roughly the same conclusion as a hearing held in June, in which Deputy Mayor Caswell Holloway defended the newly implemented, $2 billion system, asserting that it "sent the incident as the technology is designed to do."

According to the timeline published in the report, the delay was caused not by a technical failure, but by a dispatcher who didn't open the job because "it was not there or she did not see it." She then logged off the system and went on a break.

Read More: Gothamist

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