Arnold Schwarzenegger hosted some law enforcement personnel on Thanksgiving … though he wasn’t expecting them when the day started.

Law enforcement sources tell TMZ … LAPD responded to a call that a bomb had been placed in the actor-turned-politican’s mailbox at his L.A.-area home.

We’re told cops rushed to the home and searched the mailbox and surrounding area … but, they did not find an explosive device.

Our sources say officers spoke with Schwarzenegger’s security … and, we’re told they explained it’d be virtually impossible to plant a bomb at the home — given the star has round-the-clock security and video surveillance.

BTW … Arnold wasn’t at home when all this was happening — he was actually at the gym, pumping some iron before chowing down, we’re told. LAPD is treating this as a swatting … but, no arrests have been made yet.

Sources close to Arnold tell us … they’re grateful officers came to the house on the holiday to check on the situation.

It’s been a scary week for prominent figures around the country … with President-Elect Donald Trump announcing members of his cabinet had received bomb threats.

A bomb squad rushed to Congressman Matt Gaetz‘s home to check out one threat … but, it was also a false alarm.