SOUTH LOS ANGELES ( — Wayward balloons are blamed for triggering a power outage Monday, leaving  more than 5,000 Southern California Edison customers in South Los Angeles without electricity.

SCE spokesman Paul Griffo said the outage happened around 4:30 p.m. when metallic balloons got tangled in some elevated distribution lines.

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Crews were still working to return power to 5,059 homes as of 9 p.m. Power is expected to be restored by 6 a.m. Tuesday, Griffo estimated.

Metallic balloons caused 924 power outages last year for SCE, according to the utility.

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Metallic balloons always need to be tied to a weight, as required by California law.

Edison warns never tie a metallic balloon to a child’s wrist. If the balloon comes in contact with the service drop to a home or other source of electricity, it can travel through the balloon and into the child, causing serious injury or death.

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SCE suggests disposing a metallic balloon by puncturing it several times and throwing it in the trash. Do not release it.