HINGHAM, Mass. (WHDH) -- A mother was confronted with a parent’s worst nightmare when a stranger approached her son at a bus stop.

Sam Marwill, 8, was riding his bike to the bus stop when he says a stranger drove up and asked him a question.

“He said ‘hey bud, do you want to hop in the car and I can give you a ride to school,” said Sam. “And I said, ‘no, no thanks, I’m fine.'"

The man drove off, but when Sam's mom came to the bus stop a few minutes later, Sam told her what happened and she got chills up her spine.

"I was horrified, I haven’t been able to talk straight all day, frankly, because the thought of what might have been is just a horrible thought,” said mom, Laura Marwill.

Marwill reached out to neighbors to see if this might be some kind of misunderstanding but when she couldn't find anyone who might have been the driver, she called police.

"We’re not trying to create a panic. We don’t know if there actually was any criminal intent here. There may be a legitimate reason for the man to do this. He may not have intended any criminal harm. On the other side, we would rather go on the side of caution,” said Sgt. Steven Dearth.

It's an approach that's getting praise from other parents, whether it turns out to be a true danger or something else.

“Of course, we’re going to talk to the kids tonight and just make them aware of it to, you know? Just reinforce it. It’s all you can do,” said Becky Leary.

Sam said the man was in his twenties and described the car as yellow or white, with three windows on the side like a van and that it had some damage on the rocker panel between the two tires.

Police said if the exchange was innocent the man should come forward so they can put the case to rest.

If not, police said what Sam did will help other parents and children be on the lookout.