On Saturday night, a dark-blue Dodge Avenger turned onto the crowded boardwalk in Venice Beach, Calif., accelerated, and swerved around for about a quarter mile, apparently intent on hitting as many bystanders as possible. One woman was killed and 11 other injured; two are still in critical condition.

About an hour after the rampage, Nathan Louis Campbell, 38, turned himself at the nearby Santa Monica Police station. The police arrested Campbell, a transient from Colorado, on suspicion of murder. The woman killed has been identified as a 32-year-old Italian woman, Alice Gruppioni, who was visiting the Los Angeles area on her honeymoon.

"He wasn't swerving to avoid people; this guy was trying to hit people," says Sean Daly, an employee at Titanic Boutique, who witnessed the prolonged hit-and-run. "He had that look on his face with the intent to kill." Police agree that Campbell was acting intentionally, but are not publicly speculating on his motive.

Surveillance video from the Candle Cafe & Grill captured a man, apparently Campbell, parking his car, getting out for a short while, then calmly getting back in and lurching off toward the boardwalk. Some of the footage can be seen in the ABC News report above.