A 21-year-old San Carlos man was killed and four people were rushed to the hospital following a predawn accident Sunday that left a BMW split in two and the Nissan sedan it collided with upside down and teetering on an Interstate 280 concrete median wall.

The two-vehicle collision just south of Page Mill Road, reported Sunday morning by the California Highway Patrol, occurred just after 4 a.m.

CHP spokesman Art Montiel said, "the force of the collision split the BMW in half" and ejected the driver. Firefighters arrived to find Julian Thomas, the driver of a 1999 BMW, dead at the scene alongside his car after it struck the Nissan and a tree. Montiel also said that Thomas was ejected from the vehicle even though he had been wearing a seat belt.

The other passengers in the BMW, two 21-year-olds and a 19-year-old, as well as the solo driver of a 2012 Nissan, were taken to Stanford University Medical Center with "moderate and minor injuries," the CHP reported. The driver of the Nissan, Johnson Chao, of Redwood City, managed to climb from his car before emergency crews arrived.

The collision, which occurred near Los Altos Hills beneath the rolling hills of unincorporated Santa Clara County, is under investigation. It remains unknown, said Montiel, if excessive speed, alcohol or drugs were factors in the crash.

Contact Karen de Sá at 408-920-5781.