City Watch alerts come at high cost for Memphis Police

A chilling voicemail saying "I'm scared..."

A desperate mother saying, "Whoever he is, please bring her back home."

It's all Memphis Police need to issue a City Watch Alert...

Sgt. Vince Higgins with Memphis police says, "We do city watches, we do put more effort, because it's a situation where harm may have befallen person or in peril."

But late Thursday afternoon..."The mother had actually spoken with her daughter and determined she was okay, she wasn't in any danger at that moment," continues Higgins.

Nearly 24 hours of searching for a missing teen who wasn't exactly "missing".

Higgins continues, "Yes, it takes away a lot of manpower, but that's the nature of the game."

The "game" involves 800 missing persons and runaway reports EVERY MONTH..some who are actually in danger...others who aren't.

Higgins continues, "We regret having to investigate these cases that end up being false or untrue, but we have to operate....the truth."

So what about that tearful, truthful-sounding phone call?

"I can't speak to the veracity of her phone call from the beginning, situations change, especially when you're talking about adolescents, especially when you talk about runaways," continues Higgins.

"Maybe she wanted to come home at that moment, maybe she didn't...we don't know," continues Higgins.

A canceled City Watch that costs time, money and trust.