Search warrants were issued to search Michael Jackson's house ... the searches have already taken place.

The searches that took place yesterday and last Friday were performed as a result of the warrants.

The second search was triggered as a result of the interview LAPD had with Dr. Conrad Murray, according to law enforcement sources. The point of the search, in large part, was to retrieve medication.

Update...

We now know what the LAPD was after when it got a search warrant for Michael Jackson's home.

The warrant was specifically targeted to find controlled substances and paraphernalia -- in particular needles.

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