New charges of felony coercion were filed Wednesday against O.J. Simpson and three co-defendants in the alleged armed robbery of two sports memorabilia dealers.

Prosecutors increased to 12 the number of charges against Simpson, Clarence Stewart, Michael McClinton and Charles Ehrlich.

Conviction on felony coercion carries a sentence of up to six years in prison.

The four men didn't have to appear before the judge. They were represented by their lawyers.

The revised complaint drops charges against Walter Alexander and Charles Cashmore, who pleaded guilty to reduced charges and are due to testify against the others at a preliminary hearing beginning Nov. 8.