The children were safely removed from a home in the Florida city of Lakeland after a shooting on Tuesday night, Lakeland Police Captain Ed Cain told reporters.
The three dead adults all suffered gunshot wounds, Cain said, adding that all the four children are believed to be below 10 years old.
There has been no confirmation on the relationship between the three adults and the four children so far.
"It's a very tragic situation on Christmas Eve that's going to impact a lot of families," Cain was quoted as saying.
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