BRASILIA, Brazil (AP) — A towering slab of rock has broken from a cliff and toppled onto pleasure boaters drifting near a waterfall on a Brazilian lake.

Local officials said Saturday’s accident left at least six people dead and 32 injured — with as many as 20 others missing.

Video images show a gathering of small boats moving slowly near the sheer rock cliff on Furnas Lake.

Then a fissure appears in the cliff and a huge piece topples onto at least two of the vessels.

The press office of Minas Gerais state tells The Associated Press that the fire department deployed divers and helicopters to help.