James Holmes will not be able to attend a hearing scheduled for Thursday, and his attorney says it’s because of an unspecified medical condition that he developed.

Holmes is facing 152 criminal charges for allegedly opening fire during the premiere of “The Dark Knight Rises” in a movie theater in Aurora, Colorado.  The mass shooting left 12 people dead and 58 wounded.

Rob McCallum, a spokesman for the Colorado Judicial Department, said Judge William Sylvester agreed Wednesday to move Thursday’s motions hearing to December 10.

A hearing was held Wednesday to discuss rescheduling the proceeding, and defense attorneys told Sylvester that Holmes was taken to a hospital, but did not say what was wrong with their client, citing medical privilege for privacy, according to HLN affiliate KMGH.