Allen alleges in his $5 million lawsuit that the "Iron Man" actor repeatedly punched him in the face during a dispute while the pair were working on "Cat on a Hot Tin Roof" early this year, the New York Post reported Sunday.
The Jan. 24 incident at the Walter Kerr Theatre in New York began when Howard confronted Allen for unreported reasons backstage, the suit alleges.
Both Allen and Howard, who earned an Academy Award Best Actor nomination for the 2005 movie "Hustle & Flow," have both refused to comment on the alleged altercation.
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