LOS ANGELES (CBS/AP) — Authorities say two people died when the motorcycle they were on collided with a big rig on the Golden State (5) Freeway, causing a traffic tie-up for several hours.

READ MORE: Fire Crews Have Stopped Forward Progress Of 349-Acre King Fire In Lancaster, Mandatory Evacuation Orders Still In Place

California Highway Patrol Officer Christian Craycraft says the motorcycle was riding between lanes on the northbound 5 Freeway at Branford Street in Pacoima late Sunday morning when the crash happened.

Erik Scott of the Los Angeles Fire Department said a male motorcyclist and his female passenger were declared dead at the scene.

The wreck occurred as dozens of motorcyclists crowded the freeway on the 28th annual “Love Ride,” a mobile charity fundraiser.

READ MORE: Memorial Service Held For Sandra Mizer, 13-Year-Old Killed In Lucerne Valley Hit-And-Run

Craycraft says it appears the victims were riding ahead of the Love Ride motorcyclists and were not part of the charity event.

Three of the four northbound lanes were closed for nearly three hours.

Firefighters treated two people for cuts at the scene, and took another to a hospital on a backboard.

MORE NEWS: Ontario Attorney Sagi Schwartzberg Facing Federal Child Porn Charge

(TM and © Copyright 2011 CBS Local Media, a division of CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)