Fire trucks raced to Paris Hilton's Hollywood Hills home moments ago after someone from inside the house called 911 to report an emergency.

It's unclear if there was an actual fire at the home -- but we're told the root of the problem was an "electrical" issue.

We're told the call came in at 3:08 PM PST -- and trucks are still at the house.

We're told Paris was not home when the call was made.

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