The lawyer accused of a string of violent sexual assaults in Boston over 15 years ago was indicted Tuesday on new charges relating to attacks on four more women. Matthew Nilo, 35, already faced charges relating to alleged rapes against three women and the alleged attempted rape of a fourth between 2007 and 2008. He was indicted by a Suffolk County grand jury on Tuesday of seven additional offenses including a new count of rape, one count of aggravated rape, and counts of assault with intent to rape and indecent assault on battery. The charges are in connection with five attacks on four women in 2007 and 2008, with the district attorney claiming that one woman was attacked twice 11 days apart. Prosecutors say the alleged victims were attacked while walking alone in the dark at night or in the early morning. Nilo pleaded not guilty on June 15 and was released on $500,000 bail. He is set to be formally charged with the new counts at his next court appearance in July.