California declared a state of emergency after a toxic chemical leak threatened thousands. Authorities discovered a crack in a damaged tank, easing fears of an explosion and allowing many of the 40,000 evacuated residents to return.

California authorities said on Sunday they had discovered a crack in a damaged tank containing toxic chemicals, easing concerns over a potential explosion that prompted the evacuation of about 40,000 residents. The leak began on Friday in Orange County's Garden Grove area, sending fumes across a densely populated region near Disneyland.