"I took the day off to be here for my birthday," said Brook Martinez.
Amanda Clayton and Brooke Martinez spent at least two hours at Discovery Green trying to catch 'em all.
"I got 'em so it says gotcha," said Martinez, as she played on her cell phone.
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Soon, however, they will be the last few people to catch 'em all.
The Discovery Green Conservancy released a statement asking game creator Niantic to remove all stops, lures and creatures from the park. The park made the request after large crowds showed up at the park when it was closed.
"So this is 11:30 at night, an icon has just appeared and people are walking past the sign that says the park closes at 11," said Barry Mandel, President of Discovery Green.
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Mandel shared a video with Eyewitness News which shows a "Pokemon Go" icon drop after park hours as the frenzy begins. Situations like this, he said, have cost the park thousands of dollars since the app was created. The park has seen an increase in costs related to trash pickup, facility maintenance and additional overnight security.
"And then there's a group that's becoming belligerent to our security and to HPD when they are told the park is closed and it's time to leave," said Mandel.
Discovery Green received a notification last week from the creators of the game claiming the park will no longer be a stop for the avid players.
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"It kinda sucks cause it's really fun," said Amanda Clayton.
"I can understand there's some businesses that are worried about trespassing and some people are not obeying those laws," said Martinez.
Discovery Green is run by a non-profit. The president said in order to be able to afford the 600 free events yearly it offers Houstonians, it can't afford to keep paying for more security.