The Iraqi Special Tribunal set up to try Saddam Hussein said in a statement today that Mr. Hussein and three others will be referred to criminal court on charges related to the killings of about 150 Shiites in the Iraqi town of Dujail in 1982. The tribunal said that investigations into millions of documents and the questioning of thousands of witnesses have been completed, and that the trial related to the Dujail killings was one of several Mr. Hussein and his top aides are expected to face.

Officials at the tribunal have said that they expect to put Mr. Hussein on trial by the end of the year. The tribunal's chief investigating judge, Raed Jouhi, said at a news conference in Baghdad that a date for the trial would be set "within days," the Reuters news agency reported.

Today's statement represents the announcement of the first formal charges against Mr. Hussein. Other crimes for which Mr. Hussein is likely to face eventual prosecution in separate trials include the Anfal campaign of the late 1980's, in which as many as 150,000 Kurds were killed; the chemical weapons attack on the Kurdish town of Halabja in March 1988 that killed about 5,000; and the repression of a Shiite rebellion in southern Iraq in 1991, in which 150,000 people are believed to have been killed. Also under investigation by the tribunal are the executions of more than 200 Baath Party leaders after Mr. Hussein seized power in 1979.

Mr. Hussein's lawyers claim among other things that it is illegal to try Mr. Hussein in his own country because he is immune from prosecution as a head of state.