I have friends and relatives with autistic kids, and if you didn't see it yourself, you wouldn't believe how fast they can cut and run. These parents must be so relieved -- and so thankful for the "guardian angels" who surrounded this 6-year-old and kept him safe:

MOUNT VERNON – An autistic 6-year-old boy drove a miniature battery-powered ATV onto the Bronx River Parkway and was pulled over by good Samaritans on Sunday night, authorities said.

The trip started off in a city park around 7 p.m. when family members lost track of the boy, who rode off in the toy vehicle.

"They realized pretty quickly he was gone but couldn't lay eyes on him," Kieran O'Leary, spokesman for the Westchester County police, said of the Mount Vernon family.

Relatives reported the boy missing to Mount Vernon police.

At about 7:40 p.m., Westchester County police started receiving 911 calls about the unlicensed driver traveling in his vehicle — made popular by the toy brand Power Wheels — on the parkway.

He had driven to Oak Street, from a park near South Seventh Avenue, and taken the ramp onto the northbound parkway, police said.

The young driver didn't make it very far.

Three motorists slowed their vehicles to surround the boy and protect him from other vehicles that might not see him, O'Leary said. Someone was able to get out of their vehicle, and grab the boy and his ride off the parkway.

"These good Samaritans got him to the safety of the side of the road," the police spokesman said. Police officers arrived shortly after.