A man was just sitting in his seat on a Red Line train when another passenger walked up to him and fatally stabbed him before fleeing at the next stop in East Hollywood, sheriff's officials said Tuesday.
No weapon has been found and no one has been arrested in Monday's killing of 34-year-old Jose Velazco-Alvarado, officials said.
Velazco-Alvarado was stabbed about 9:18 a.m. and taken to a hospital in grave condition when the train stopped at the Vermont/Santa Monica station, said Metro spokesman Marc Littman.
A security camera captured a brief conversation between Velazco-Alvarado and the assailant just moments before the stabbing.
"There was a verbal exchange," said Det. Keith Schumaker of the Los Angeles CountySheriff's Department's Transit Bureau.
"The victim was reportedly sitting in a seat on the train as it approached the train station. The suspect approached the victim and stabbed him one time before exiting," sheriff's officials said in a statement.
The assailant was described as between 18 and 24 years old.
A woman told The Times a few hours after the incident that she witnessed the attack and that it was "quite traumatic."
The woman, who asked not to be identified out of fear of retaliation, said she was standing by the door when she saw the suspect singing loudly in the car.
He "walks down the aisle to the middle section and was standing there singing really loud rap music," the woman said. "I particularly noticed because I was watching, thinking, 'That's aggressive and loud.'"
She then saw the man stab the victim, later identified as Velazco-Alvarado, in the neck.
Craig Harvey of the Los Angeles County Coroner's office said Tuesday an autopsy had yet to be performed on Velazco-Alvarado.
On Tuesday, Metro officials released a statement saying they were "very saddened" to learn Velazco-Alvarado had succumbed to his injuries.
"This is a very tragic incident that occurred and Metro remains committed to working closely with the LASD to ensure that the individual involved in this incident is caught and prosecuted to the full extent of the law," according to the statement.
Metro officials urged anyone who witnessed the incident or has information to contact the sheriff's Homicide Bureau at 323-890-5500.
Officials said Monday's homicide was only the second on the subway since the line's service began in 1993.