emirates7 - About 40,000 people were under evacuation orders and schools shut down Friday in Southern California after a storage tank continued to leak a hazardous chemical used to make plastic parts that officials said could rupture or explode.

A storage tank holding between 6,000 and 7,000 gallons of methyl methacrylate overheated Thursday and began venting vapors into the air at an aerospace plastics facility in Garden Grove, a city in Orange County, the county's fire authority said.

Officials ordered residents in Garden Grove to leave and expanded evacuations orders Friday to some residents of five other Orange County cities — Cypress, Stanton, Anaheim, Buena Park and Westminster — after being unable to stop the leak overnight on the tank at GKN Aerospace, which makes parts for commercial and military aircraft.

No injuries or deaths have been reported, authorities said.

"We're doing our best to figure out when or how we can prevent it,'' said Garden Grove Fire Chief Craig Covey during a Friday afternoon press conference.

According to AP, Covey said crews have created containment barriers with sandbags in case there is a chemical spill from the tank to prevent the chemical from getting into storm drains or reaching creeks or the nearby ocean.

He said the chemical is highly volatile, toxic and flammable.