DIAMOND BAR (CBSLA.com) — Authorities Saturday said a woman was killed in a crash on the 60 Freeway in Diamond Bar.

The two-vehicle crash on the freeway occurred on the westbound lanes just east of State Route 57 about 7:48 a.m., according to the California Highway Patrol.

READ MORE: Man, 52, Taken Into Custody After Alleged Bomb Threat At U.S. Post Office In Oxnard

Authorities say a car with four occupants was rear-ended in the HOV lane at a high rate of speed. Police said the vehicle had slowed for an unknown reason before being struck from behind.

The car then hit the center divider and slid 60 yards before coming to a stop. The CHP said the driver of the second vehicle exited the freeway and dialed 911. Authorities initially reported the accident as a hit-and-run.

READ MORE: Up-And-Down Chargers Hold Off Bengals For 41-22 Victory

The CHP described the deceased as a Hispanic woman about 25 to 30 years old. She died at the scene.

The other three people in the first vehicle were taken to UCI Medical Center. The extent of their injuries was not known.

The crash initially blocked four lanes of the thoroughfare, prompting the issuance of a SigAlert. As of 9:45 a.m., three lanes remained blocked.

MORE NEWS: AP: Chris Cuomo Accused Of Sexual Harassment Days Before CNN Firing

No further information was immediately available.