WARNING: An unauthorized butt enhancer may be on the loose in Manhattan. The Post breaks an EXCLUSIVE story this morning about Kimberly Smedley, a wanton, unauthorized woman with no medical training who offers black market silicone injections out of an East 39th St. hotel. For $1,600, Smedley promises women "J.Lo butts." But if it sounds too good to be true, it probably is.

"I need to see your butt," Kimberly Smedley told a Post reporter posing as a customer last week in a suite at the Eastgate Tower Hotel on East 39th Street.

Smedley, a heavyset woman wearing camouflage pants and fake Ugg boots, then demanded $1,600 in cash to give nine injections to each cheek...

When it was her turn, [one] woman lay face down on a couch, in view of the others, while Smedley gave her about 10 shots on each side.

"I wanted a J.Lo butt - full, round and high," the woman said.

The injections gave her the "lift" she wanted - at first. But now she is seeing doctors for many hard lumps, ripples and skin discolorations that have developed on her rear.

BEWARE.

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