The US has begun mourning after 12 people were killed and 58 wounded in a shooting at a midnight showing of the new Batman film, the Dark Knight Rises.
US President Barack Obama ordered flags flown at half mast and said the day was "for prayer and reflection".
A man wearing a gas mask and body armour threw tear gas canisters at movie-goers in Aurora, Colorado, then fired on the crowd, witnesses said.
James Holmes, 24, was arrested outside the cinema near Denver, police said.He will appear at Arapahoe County District Court, in nearby Centennial, Colorado, on Monday at 09:30 local time (15:30 GMT).
In a briefing at the end of a difficult day in Colorado, an emotional Governor John Hickenlooper confirmed that the casualty figure had been revised down one, to 70 people killed or injured.
Thirty people remained in hospital, Mr Hickenlooper said, with 11 of those in a critical condition.