Sources at Warner Bros. studios told CNN the company made a "substantial" donation. Warner Bros., a subsidiary of CNN's parent company Time Warner, would not divulge how much money it was giving out of respect for the victims, the sources said.

Shooting suspect Holmes booby-trapped his Aurora apartment with more than 30 homemade grenades and 10 gallons of gasoline, a law enforcement official who viewed video showing the apartment's interior has told CNN.

The sophisticated setup inside the sparsely furnished third-floor, one-bedroom apartment was meant to harm, or possibly kill, anyone who entered -- and tested the skills of bomb squad members charged with clearing it, the official said.

Tenants of the three-story, brick apartment building were allowed to return Wednesday night to sleep in their apartments for the first time since early Friday, when police went door-to-door and rousted them.

The Holmes family issued a statement Friday saying, "Our hearts go out to those who were involved in this tragedy and to the families and friends of those involved." It added, "We are still trying to process this information."