The Multnomah County district attorney’s office announced new charges Tuesday against a man prosecutors believe killed several women in the 1980s.

The new charges against Homer Lee Jackson, 59, allege that in 1993 he also killed 29 year-old Lawauna Triplet.

In 2015, Jackson was indicted on 12 counts of aggravated murder for the deaths of four women between 1983 and 1987: Essie Jackson, 23; Tonya Harry, 19; Angela Anderson, 14; and Latanga Watts, 27.

All were African American, and all died by asphyxiation or strangulation, according to police.

At the time, the alleged victims were believed to be engaged in prostitution in North Portland. Some were victims of sex trafficking, police said.

Jackson sufferers from schizophrenia. In December, the Oregon Supreme Court tossed out confessions Jackson made because of the tactics used by police officers at the time.

In the new indictment, prosecutors dismissed counts involving Essie Jackson, who was included as one of the four women in the 2015 indictment.

The Multnomah County district attorney’s office declined an interview on the matter, but in a release said even though the office is not prosecuting her case anymore, they believe Jackson is a suspect in her death.

The Portland Police Bureau’s cold case homicide unit is continuing to investigate.