An investigation is underway in Fullerton after four people were found dead from a possible overdose, police said.

They were called to the 100 block of W. Wilshire Avenue at around 11 a.m. after receiving a call from a person who said "his friends had overdosed and were not breathing," according to a news release from the Anaheim Police Department.

Upon arrival, officers found four people dead inside of a home. None of the victims has yet been identified.

"Fullerton Police Department Detectives responded and are conducting a death investigation," the release said. "There is no immediate threat to the public."

This is a developing story. Check back for details.

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