A school resource officer was standing in a crosswalk when students were leaving school for the day. The resource officer, Connecticut police officer Carlos Carmo Jr., saw a runaway SUV with no driver and two helpless passengers inside.

Carmo heroically jumped into action to keep the students from being run over.

Security video of what happened is amazing:

“We go through a lot of scenarios, but that’s not a scenario they teach us in the academy,” Carmo said on Monday in an interview on ABC’s “Good Morning America.” “That’s just one of those things where your instinct kicks in and you basically do what you got to do to keep these kids safe.”

I was just thinking in my mind, ‘I got to find a way to stop this’

An investigation later determined that the vehicle had been parked on Boston Avenue when, for some unexplained reason, it accidentally slipped out of park, merged into eastbound traffic and began to pick up speed on the downhill slope with one person in the passenger seat and another in the back seat but no one at the wheel, according to police.