We’re told the actor’s L.A. home was burglarized Wednesday evening … with LAPD responding to an anonymous call about a possible trespasser at his property at around 7 PM. Cops arrived on the scene, and conducted a search, but found no one.

But, we’re told police were back there again around 1 AM when an alarm sounded on the property … and this time officers say multiple men in ski masks were spotted on security cams smashing a window and entering the house.

According to our sources, the culprits took one firearm from the home before making a run for it. It’s unclear if anything else was taken, but Keanu was not home at the time.

[Come on, man. Reeves is one of the coolest dudes in Hollywood. He has a reputation of treating everyone with courtesy and respect and generally minding his own business. Too bad we don’t have more people like that around, especially these culprits. It did remind me of Reeves’ movie “Knock Knock,” which is a very suspenseful psychological-horror flick if you can get past the nudity. — Ed]