(LOS ANGELES) -- Los Angeles police are investigating a threatening letter sent to CBS late-night host Craig Ferguson's studio.
According to E! News, two people at the CBS complex in L.A. where Ferguson's Late Late Show is taped were briefly quarantined Tuesday afternoon after they were exposed to what turned out to be a harmless powder inside the envelope.
Police believe the letter, which included threats against Ferguson, may have been sent from Europe. Ferguson, who's Scottish by birth but a naturalized American citizen, recently taped episodes of his show in Paris.
Ferguson tweeted Tuesday, "Ack! Someone mailed my show white powder & claimed it was anthrax. I'm not a big fan of that sort of thing."
A death threat against Ferguson's fellow CBS late-night host David Letterman, whose production company produces Ferguson's show, was recently posted on a jihadist website.
Copyright 2011 ABC News Radio