Many left gifts of cash in a heart-shaped box.
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"We were by the entrance taking pictures with guests, quite distracted and quite busy at the moment," said newlywed Anh Bach.
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Surveillance video shows a man entering the restaurant, grabbing the gift box and then running out the door.
"One of my friends told me like, 'Oh, they took the money,' so then I instantly just ran out the door and tried to chase after him," said groom Kenny Diep.
"I almost fainted," said Bach. "I was in disbelief that it was happening."
The thief got away with around $20,000.
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"What hurts most is I want to be happy the whole night and I know everybody was feeling pretty bummed out the whole night," said Diep.
The couple had hoped to use the money to take a honeymoon trip to Japan and Vietnam with family members and pay wedding expenses.
"It took us over a year to plan the wedding and a few years to save up for the wedding so something like this was devastating," Bach said.
Now, they're hoping someone will recognize the suspect and help the police capture him.
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