According to Southampton Town Police, $4,000 in cash was taken from a briefcase belonging to the couple, who have been dating since 2007 and are the parents to Mason, 4, and Penelope, 2.
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"We believe the money was stolen from the briefcase in the residence," a representative for the Southampton Town Police tells Us. "We do not believe anyone was home at the time of the incident."
Kardashian, 35, and Disick, 31, have been spending time in the Hamptons this summer while members of the Kardashian family film the reality program "Kourtney and Khloe Take the Hamptons".
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"The charge is Grand Larceny Third Degree because of the amount of money -- $4,000 -- that was removed from a briefcase," the rep added. "The crime was reported on July 8th. It's an ongoing investigation… We do not have any leads as to who stole the money."