America Online Inc. said Thursday it had filed a federal lawsuit accusing numerous unnamed defendants of violating federal and state laws by sending bulk messages known as “spim” to instant message accounts and Internet chat rooms.

The lawsuit, filed late Wednesday in federal court in Alexandria, Va., marked the first time AOL has expressly targeted spim in a legal action.

AOL and its Anti-Spam Alliance partners — EarthLink Inc., Microsoft Corp. and Yahoo Inc. also said Thursday that they had filed another series of lawsuits targeting spam, the bulk e-mail messages that can clog e-mail inboxes and annoy some users. The lawsuits were filed in courts in Georgia, Virginia, Washington and California.