What accusation does Tiresias make?

In Sophocles' play Oedipus Rex, the blind prophet Tiresias accuses Oedipus of being the cause of the plague that has recently fallen over Thebes. He states that Oedipus has unknowingly killed his father and married his mother, and thus brought divine punishment upon the city. Tiresias also tells Oedipus that the only way to end the plague is for Oedipus to exile himself from the city and never return.

Tiresias' accusation is that Oedipus has committed an act of incest and patricide, and as a result, is responsible for the plague that has befallen Thebes. He believes that the only way to end the plague is for Oedipus to exile himself from the city and never return.