President Obama is vowing to use "whatever power his office holds" to protect the nation's children from gun violence.

Obama said he plans to engage with law enforcement, mental health professionals, parents and educators in the coming weeks.

Meanwhile, Sen. Dianne Feinstein, D-Calif., plans to introduce legislation to ban new assault weapons.

Colorado Gov. John Hickenlooper said his state has put new safeguards in place to help identify potentially dangerous individuals after the theatre shooting in Aurora.

On CNN, Hickenlooper described nearly $20 million in new programs that aim "to put more support for people with mental illness."

"(They are) to make sure we have a 24-hour hotline that someone can call in if they think someone appears unstable, a danger to themselves, or others," he said.

Outgoing Sen. Joe Lieberman, I-Conn., said there needs to be a national commission on mass violence that studies, among other problems, the impact of violent video games and movies.

"I spent enough time on this question of violence, and the entertainment culture, to reach this conclusion: that the violence in the entertainment culture, particularly with the extraordinary realism to video games and movies now, does cause vulnerable young men, particularly, to be more violent," Liberman said.

Debate on gun control is already heating up in the aftermath of the Connecticut shooting.