Prosecutors in the case of James Holmes, the accused Aurora, Colorado, gunman, have filed a motion to add 10 charges to more than 140 he already faces, a state court official said Wednesday.
The state is also seeking to amend 17 of the original charges, Rob McCallum, a public information officer with the Office of the State Court Administrator.
If added, the new charges would bring to 152 the counts against Holmes.
Holmes is accused of opening fire July 20 in Aurora during a midnight premiere of the latest Batman movie, "The Dark Knight Rises," killing 12 people and injuring 58. Holmes, 24, has been charged with murder and attempted murder and also faces weapons charges.
He is scheduled to be in court at 9 a.m. (11 a.m. ET) Thursday for a motions hearing.
The prosecution and defense argued for many documents in the case to remain sealed -- the former to assure the integrity of the continuing investigation, and the latter to protect Holmes' right to a fair trial. A judge granted the gag order on August 13.