LOS ANGELES — Authorities say a teenage boy who struck a bridge while standing on the top section of a double-decker tour bus has died.

JUST IN: Teen hurt on double-decker Starline bus has died, coroner confirms http://t.co/trJAcZkFQipic.twitter.com/ZQ5l4HQpO3

— NBC Los Angeles (@NBCLA) July 13, 2014

The Los Angeles Times reported Sunday that 16-year-old Mason Zisette was standing on the tour bus Thursday evening as it passed under a bridge on the 405 freeway in Inglewood.

The Los Angeles County coroner’s office says Zisette died Saturday afternoon. The cause of death has not yet been determined.

The California Highway Patrol says the Star Line Tours bus had about 45 passengers, and most were under 18 years old.