(CNN) -- Ohio prosecutors announced new charges against accused serial killer Anthony Sowell on Thursday in connection with the rape of a 34-year-old woman in his Cleveland, Ohio, home.
Sowell already faces murder, attempted murder, rape and attempted rape charges in connection with the killings of 11 women and attacks on four other women. He was arrested after the bodies of the slain women were found at his house last fall, and he has pleaded not guilty by reason of insanity.
The grisly discoveries in Sowell's home have led to the case being called a "house of horrors."
The latest indictment, which includes 10 counts, brings the total number of criminal charges against him to 95. No details of the new indictment were immediately released.
Sowell served 15 years in prison for a 1989 attempted rape and was released in 2005. He was required to register as a sex offender.
Cuyahoga County Prosecutor Bill Mason has said that his cold case unit is reviewing unsolved murders that occurred during the time Sowell lived in Cleveland and East Cleveland, Ohio, to see whether there are any connections. Mason said the group is working its way through 75 cases.
He said evidence is not scheduled to be presented until June for the initial case involving 85 charges.
Most of the women whose remains were found in Sowell's home were strangled by ligature -- which could include a string, cord or wire -- and at least one was strangled by hand, officials said. Seven still had ligatures wrapped around their necks. A skull is all that remains of one victim. It was found wrapped in a paper bag and stuffed into a bucket in the home's basement.