The man accused of killing 12 people and wounding 58 others in a Colorado movie theater in the western Unites States is scheduled to make his first court appearance Monday, as investigators continue to piece together the events leading up to the shooting.

James Holmes has been held in solitary confinement since police arrested him early Friday outside the theater in Aurora, Colorado, near Denver.

Police say Holmes was dressed in body armor and carrying multiple guns when he opened fire on a crowd watching the film The Dark Night Rises.

Authorities say all of the weapons were purchased legally.

President Barack Obama met privately with victims' families Sunday. He later gave an address saying he was there more as a father and a husband than as a president, and that these incidents resonate because people can understand how they would feel if it were their loved one who was killed.

Mr. Obama said he hopes that in the days and months to come, Americans reflect on how to address “the senseless violence” that mars the country.

The president and Republican presidential candidate Mitt Romney temporarily pulled their campaign commercials from Colorado television following the attack, out of respect for the victims.

The shooting has renewed gun control debates in the United States, particularly the lack of regulation on buying ammunition online. Authorities say Holmes bought thousands of bullets from websites in the months leading up to the attack. Proponents of such sales say it is legitimate for sportsmen to buy large amounts of ammunition that way.