At 11:38 eastern time, a Mooney M20J was damaged during a forced landing shortly after takeoff from Danbury Municipal Airport. The pilot was seriously injured and the two passengers were not injured. The pilot told investigators that, at 600 to 700 feet, the engine began running rough, then quit. The pilot then landed the airplane in a swamp. The pilot also said the airplane had sat on the ramp for about 2 weeks, and that he did not check the fuel tanks for water prior to departure.