Crews urgently try to prevent leak or explosion of chemical tank in California, where thousands are evacuated

CNN, KABC, KCAL, KCBS, @OCFIREAUTHORITY, X, GKN AEROSPACE, MIGUEL LOO, KCAL/KCBS, @OCFireAuthority/X By Nina Giraldo, Taylor Romine, Emma Tucker, Alaa Elassar, CNN (CNN) — Crews in Southern California are again working through the night to stop a massive tank filled with a toxic chemical from leaking or causing a catastrophic explosion as tens of thousands