Officials said that they were working with physical evidence, including DNA, and that they were seeking a second man who appeared to have crossed paths with the possible suspect.
A memorial on the Brown University campus in Providence, R.I., on Wednesday.
Lawyers for Rex Heuermann, who is charged with killing seven women, made last-ditch attempts to toss crucial evidence, but prosecutors are preparing for an expected trial next year.
Lawyers for Rex Heuermann, right, tried to persuade a judge to divide the case into as many as five separate trials.