Thousands were without power Monday night in Southern California, and at least one major outage was caused by Mylar balloons.
About 5,000 customers in an unincorporated part of South Los Angeles lost power about 4:30 p.m. because metallic balloons were caught in the electrical equipment, according to Southern California Edison.
The power is estimated to return by 6 a.m. Tuesday, according to the utility.
Metallic balloons are increasingly disrupting power to customers across the electrical grid, according to the utility. In 2015, Edison had 924 outages caused by metallic balloons, up from the previous high of 714 in 2012.
In the days leading up to Valentine's Day, Edison warned customers not to release metallic balloons into the sky or to tie the balloons to a person's wrist, which poses the risk of electrocution. The utility also advised proprietors to attach weights to metallic balloons.
"Metallic balloons look harmless, but there's no way to overstate how dangerous they can be when released outside," Paul Jeske, the utility's director of corporate health and safety, said in a statement.
Other communities across the Southland were also affected by outages.
About 2,000 customers in Seal Beach lost power about 7 p.m., and Southern California Edison estimated power would be restored by 11:30 p.m. The cause of the outage was under investigation.
In Long Beach, about 3,854 customers lost power starting at 7 p.m. By 9:15 p.m., the number of outages there fell to about 1,775, and the utility estimated power would be restored by 10:30 p.m. It's unclear what caused the outage.
In Ontario, about 500 customers lost power about 8 p.m. because of equipment upgrades, the company said. Power was estimated to be restored by 6 a.m. Tuesday.
If a balloon or another item becomes caught in power lines, the company has advised customers to call (800) 611-1911.
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