Washington, Jul 23 (IANS): US President Barack Obama Sunday left Washington for Colorado state's Aurora city to meet families of the victims of the deadly shooting in which 12 people were killed Friday.

Obama left Washington a day earlier than previously planned for a three-day campaign swing into the west of the country. He will also meet with families of the shooting victims and local officials, before flying to San Francisco for the night, Xinhua reported.

Police have already taken the suspect, identified as James Holmes, 24, into custody and defused all dangers in his booby-trapped apartment.

Obama has called the tragedy a "heinous crime" that was " senseless" and "beyond reason". He pledged to seek justice while ordering that US flags be flown at half-mast for six days.

He and Republican presidential candidate Mitt Romney both called off their election campaign events Friday, as the country dealt with the aftermath of the shooting.