LEMON GROVE, Calif. -- As the Lemon Grove Little League team gears up for Sunday's game playing ball isn't the only thing on their minds.

“It kinda freaks me out to think that ‘whoa, is there someone behind me?” Leah Shiflet said.

The girls say they’ve seen the social media posts and are spooked.

“I’ve heard stories from my friends at how they saw clowns. It's kinda creepy, and it's just weird. I don't get why people would do that,” Leia Bourne said.

People in more than two dozen states have reported seeing the creepy characters. In most cases it's all a hoax, but it has turned serious in others.

Authorities in Greenville, South Caroline, were among the first to report a clown-related incident. Late last month, some children reported clowns trying to lure them into the woods with money. Sheriff's deputies found no evidence, however -- not even a prankster in a clown suit.

Texas State University sent a letter to students warning them someone was attacked at a housing complex by a man wearing a clown costume.

In Philadelphia, police took a 13 year-old girl into custody for allegedly using scary clowns on social media to threaten local schools.

“It kinda makes me concerned, like at night I kinda feel like it’s hard for me to sleep. If I hear something I'm like ‘whoa,’ or if I have my light on they'll see out my window,” Leah Shiflet said.

The girls say they hope the clown craze doesn't turn violent and that eventually it will lose popularity. Until then, they plan to be extra vigilant, especially with Halloween just weeks away.

“I am concerned about people around me and how they might be attacked by a clown, or how I might be attacked by a clown. It's weird it's like a horror movie,” Bourne said.

“There's a lot of crazy people out there that have sick minds that just like to do things for their own crazy pleasure. It just has me thinking like why?” Shiflet said.

San Diego and Chula Vista police say they haven’t received any reports of clown sightings, but are prepared for a possible threat.

Meanwhile, there are groups forming to try to get the message out that clowns should not be feared. For example, organizers in Arizona are putting together a "Clown Lives Matter" march as a "peaceful way to show clowns are not psycho killers."

The hashtag #ClownLivesMatter is also circulating on social media channels, like Twitter.