Two motorcyclists killed in multi-vehicle crash on 5 Freeway

Two motorcyclists were killed in a crash on the 5 Freeway in Irvine on Sunday. 
The crash happened at around 12:15 a.m. on northbound lanes near Culver Drive, according to the California Highway Patrol. 
Officers were sent to the area after learning of a rider down in the middle lane, the department said. 
They arrived to the scene, where there were approximately 50 motorcyclists on hand, officers said. 
A short time after they arrived a second person was pronounced dead at the scene, leading them to issue a SigAlert for all northbound lanes. 
It lasted until around 4 a.m. when all lanes were reopened. 
No information on the moments leading up to the crash was available.