Lakeland, Florida - Two giant sinkholes almost completely drained a lake, leaving dead fish rotting on oozing mud flats and alligators and snapping turtles fighting for their lives.

Scott Lake began draining last week, and the larger of the two sinkholes grew this week to at least 60m wide and five metres deep, claiming a dock, concrete walkway and chain-link fence.

"It's heartbreaking," said Linda Logan, a member of a local homeowners' association.

The 291-acre natural lake is owned by the surrounding homeowners south of Lakeland, 50km east of Tampa. Residents formed a committee to figure out what to do.

The lake could be restored. If the sinkholes are filled in, rain and runoff would refill the lake, but that could take years, and experts say they would have to wait for the lake to finish draining first.

Sinkholes form when groundwater levels drop, leaving empty crevices and cavities in the limestone aquifer. - Sapa-AP