The letter said the package, containing a butt plug and vibrator, posed "an immediate danger to life or limb".
Netizens urged authorities to put up signs around the area.
"I'm Filipina. Of course my English is good. But when I arrive in Thailand, it’s f***ing useless," she said.
No casualties were immediately reported.
The NEA said it has "strengthened enforcement presence" in the area.
The Mandopop star laughed off his ultra-brief exit, applauding his opponent and signing autographs for fans.
Authorities said the fabricated image damaged the reputation of the landmark.
The woman believes the baby is a boy and is her late son's reincarnation.
A witness saw the boy drifting with the waves for 200m until he disappeared from sight.
The post claimed the child wanted the shoes after seeing her classmates wearing similar black, branded school footwear.