San Diego Police say a man has been following women and peering into windows in the Hillcrest and Mission Hills areas.

Sheryl Smith took video of the man, and she says people have posted about frightening run-ins with him around Mission Hills and Hillcrest on the Nextdoor app.

"He follows them, makes them feel very ill at ease, enough for them to sprint away from him," said Smith. "He's peered into windows."

Smith says she reported the man to police and they know exactly who he is.

"She said that she looked up his history and he has an extensive criminal history," Smith said.

But according to police, that criminal history was in northern California when he was younger.

Police said the man hasn't done anything illegal here, so police told Smith they cannot arrest him. Being creepy is not a crime.

The man was captured on surveillance video acting bizarrely, and what worries Smith is they have no idea what could set him off.

"We have to wait for something terrible to happen, which is what is so disconcerting," Smith said.

Neighbors can't control where the man goes or what he does, but they said they will keep each other informed about him through the Nextdoor app.