Federal investigators were sifting through the wreckage Sunday of a helicopter crash at a well-known movie and TV production ranch that killed three people.

The 3:40 a.m. local time (6:40 a.m. ET) crash happened on the site of the Polsa Rosa Movie Ranch in Acton, Calif., on the northwestern edge of the Angeles National Forest about 30 miles north of Los Angeles.

Read more: NBC News