A man fatally stabbed his step-father, ex-girlfriend and her mother, before running over a pedestrian, in a 28-hour rampage in New York City, police said.
The man, alleged to be Ukrainian-born Maksim Gelman, 23, was armed with five knives when he went on a stabbing spree early Friday, officials said.
Four other people were also knifed but survived the attacks.
Mr Gelman was finally arrested on a train on Saturday morning after a all-night manhunt, police said.
Charges against him are pending.
"It's so horrendous and bizarre. We have no reason to know why he did this," said Police Commissioner Raymond Kelly.
He said had not recalled seeing "anything like this" in the decades he had worked for the New York police department. BBC News
