ONTARIO (CBSLA.com)  —  Authorities said shots have been fired inside a home where they said an incomplete 911 call was traced.

Gordon Spencer in Sky9 said officers were dispatched to the 900 block of N. Vesta in Ontario Sunday evening just before 9 p.m. Sunday.

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When they arrived they heard shots; not sure if they were fired at police.

A large perimeter was set up.  Many streets have been blocked off, including nearby Holt Street where police have also set up a command post.

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Spencer saw some people exiting the home. It was unclear if they were family members or neighbors.

SWAT team and Ontario Police officers have the home surrounded, Spencer reported.

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