Updated

A federal judge says a northeast Texas woman accused of sending ricin-laced letters to President Barack Obama and New York Mayor Michael Bloomberg is competent to stand trial.

U.S. Magistrate Judge Caroline Craven said Shannon Guess Richardson is mentally competent for a trial during a brief hearing Wednesday in Texarkana.

Richardson is accused of sending the letters to Obama, Bloomberg and a man who heads Bloomberg's gun control organization.

Richardson also pleaded not guilty Wednesday to two counts of mailing a threatening communication and one count of making a threat against the President of the United States.

A federal affidavit alleges Richardson called authorities to implicate her husband before she was arrested in June.

Richardson's next court hearing is Sept. 11.