(Image Credit: Arapahoe County Sheriff/AP Photo)

ABC News' Clayton Sandell and Carol McKinley report:

Accused Aurora, Colo., theater shooter James Holmes, 24, was taken to the hospital Tuesday after he tried to harm himself by ramming his head into the wall of his jail cell, sources told ABC News.

Holmes was taken from his jail cell to a hospital for treatment and is now back in his cell, the sources said. He is able to move and talk.

In a hearing today, Holmes' defense attorneys said their client was in no condition to appear in court Thursday but would not say what why.

Arapahoe County District Judge William B. Sylvester granted a continuance and postponed the Thursday hearing until Dec. 10.

Prosecutor Rich Orman had objected to the motion, saying the defense should be required to reveal Holmes' condition before asking for a continuance, The Associated Press reported.

Holmes has been charged with killing 12 people and injuring at least 58 people after he opened fire inside a movie theater July 20. He has yet to enter a plea.

The Associated Press contributed to this report.