SACRAMENTO (CBS13) — Two local moms posted warnings on social media after they believe their children were targeted by possible human traffickers at busy grocery stores.

There were two separate incidents — one happened in Sacramento and one in Roseville. The Roseville post went viral, and police are now getting involved, trying to calm concern and let parents know how to protect themselves and their children best.

Julia, the mother who posted a warning, said, "It made me sick to my stomach."

They were terrifying moments for the mother when she feared human traffickers were targeting her son at the Walmart store on El Camino and Watt avenues in Sacramento.

"I was afraid that they were going to try and take him," she said.

Julia says two men were lurking around, popping up at every aisle she was in and standing just feet away from her 2-year-old son while staring directly at him.

"For anyone to be staring at your child to the point it makes you uncomfortable, is pretty scary," said Julia.

She says it continued until they left the store. She later posted her experience on Facebook in hopes of raising awareness for other parents.

One mother, Terri Self, said: "That's creepy — makes you not feel safe in the world."

Just days before Julia's post, another local mom feared her children were also the target of a possible human trafficker. In this case, she was at Whole Foods on Galleria Boulevard in Roseville when she said a suspicious man in his car was staring at her and her three young children. Her post went viral and was shared more than 20,000 times. It also caught the attention of the Roseville police department.

Roseville Police spokeswoman Dee Dee Gunther said, "We were starting to get a lot of inquiries from our residents asking if it's safe here, should we be worried about our children being stolen?"

Gunther says it's rare for sex traffickers to abduct children, and there's no evidence that that is happening in Roseville. She also says anything is possible.

So, what should parents do if they see someone appearing to target their children?

"If a mom thinks something is suspicious, it's suspicious, and we really encourage them to call us right away so we can check it out," said Gunther.

Julia says she hopes every parent will pay more attention and trust their instincts like she did. She also says she did not notify Walmart or police because her focus was getting out of the store. In hindsight, she says she would have notified the store and authorities sooner. Roseville police say even if a crime isn't committed, they encourage suspicious person calls and often respond to them.