Cops discovered "the rear glass sliding door appeared to have been forced open," said the source, and the home "appeared to have been ransacked."
There were no residents in the home, the source said.
And RadarOnline.com has discovered the reason why! Disick, who has been trying to sell the secluded nearly $6 million bachelor pad, according to another source, was in Vegas starting to party for his birthday!
Although Kourtney Kardashian's baby daddy doesn't officially turn 34 until Friday, May 26, "he was starting the celebration early," said a source.
"The thieves struck when he was in Vegas," the source noted, and now, that has made the Kardashians very nervous.
"The Kardashians fear it was another inside job," said the source.
As RadarOnline.com has reported, after Kim Kardashian was robbed in Paris last year, reports swirled that a member of the family's inner circle might have betrayed them.
Kim and husband Kanye West's former New York bodyguard, Steve Sanulis, said he believed that shocking robbery could have been orchestrated by a friend or family member who knew everything about her whirlwind Paris fashion week trip.
Could the same be true when it comes to the burglary of the home of Kourtney's ex-boyfriend Disick?
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